0001193125-25-258666 | 10-Q | XBRL Viewer

Debt and Financing Arrangements

9 Months Ended

Sep. 30, 2025

(5) Debt and Financing Arrangements

At September 30, 2025 and December 31, 2024, debt consisted of the following (in thousands):


	September 30, 2025		December 31, 2024
Credit Arrangements, described below	$	218,000	$	194,000
Finance Leases		1,199		6,294
Total debt		219,199		200,294
Less: current portion of long-term debt		1,199		5,313
Long-term debt, less current portion	$	218,000	$	194,981

The Company’s liquidity needs arise primarily from capital investment in new equipment, land and structures, information technology and letters of credit and surety bonds required under insurance programs, as well as funding working capital requirements.

Credit Arrangements

Revolving Credit Facility

The Company is a party to an unsecured credit agreement with its banking group (the Revolving Credit Facility). On December 9, 2024, the Company entered into an amendment to the Revolving Credit Facility. The amendment increased commitments under the Revolving Credit Facility by $300 million to an aggregate commitment of $600 million and expanded the accordion feature, subject to certain conditions and availability of lender commitments, from $150 million to $300 million. This amendment also extended the maturity date of the Revolving Credit Facility from February 3, 2028, to December 9, 2029. Borrowings under the Revolving Credit Facility bear interest at the Company’s election at a variable rate equal to (a) one, three or six month term SOFR (the forward-looking secured overnight financing rate) plus 0.10%, or (b) an alternate base rate, in each case plus an applicable margin. Additionally, the amendment adjusted the applicable margin such that the applicable margin is now between 1.25% and 2.00% per annum for term SOFR loans and between 0.25% and 1.00% per annum for alternate base rate loans, in each case based on the Company’s consolidated net lease adjusted leverage ratio. The amendment also modified the fees that the Company accrues based on the daily unused portion of the credit facility, which will now range between 0.175% and 0.30% based on the Company’s consolidated net lease adjusted leverage ratio. The Revolving Credit Facility contains certain customary representations and warranties, affirmative and negative covenants and provisions relating to events of default. Under the Revolving Credit Facility, if an event of default occurs, the banks will be entitled to take various actions, including the acceleration of amounts due. Under the Revolving Credit Facility, the Company is subject to a maximum consolidated net lease adjusted leverage ratio of less than 3.50 to 1.00 with the potential to be temporarily increased in the event the Company makes an acquisition that meets certain criteria. The Company was in compliance with its debt covenants under the Revolving Credit Facility at September 30, 2025.

At September 30, 2025, the Company had outstanding borrowings of $118.0 million and outstanding letters of credit of $36.4 million under the Revolving Credit Facility. At December 31, 2024, the Company had outstanding borrowings of $94.0 million and outstanding letters of credit of $32.2 million under the Revolving Credit Facility. At September 30, 2025, the Company had $445.6 million in availability under the Revolving Credit Facility.

Private Shelf Agreement

On November 9, 2023, the Company entered into a $350 million uncommitted Private Shelf Agreement (the Shelf Agreement) with PGIM, Inc. (Prudential) and certain affiliates and managed accounts of Prudential (the Note Purchasers), which allows the Company, from time to time, to offer for sale to Prudential and its affiliates, in one or a series of transactions, senior notes of the Company, through November 9, 2026.

Pursuant to the Shelf Agreement, on May 1, 2024, the Company issued senior promissory notes (the Initial Notes) in an aggregate principal amount of $100 million to the Note Purchasers. The Initial Notes bear interest at 6.09% per annum and mature on May 1, 2029, unless repaid earlier by the Company. The Initial Notes are senior unsecured obligations and rank pari passu with borrowings under the Revolving Credit Facility or other senior promissory notes issued pursuant to the Shelf Agreement.

Additional notes issued under the Shelf Agreement, if any, would bear interest at a rate per annum, and would have such other terms, as would be set forth in a confirmation of acceptance executed by the parties prior to the closing of the applicable sale transaction.

The Shelf Agreement requires that the Company maintain a consolidated net lease adjusted leverage ratio of less than 3.50 to 1.00, with limited exceptions. The Shelf Agreement also contains certain customary representations and warranties, affirmative and negative covenants and provisions related to events of default. Upon the occurrence and continuance of an event of default, the holders of notes issued under the Shelf Agreement may require immediate payment of all amounts owing under such notes. The Company was in compliance with its debt covenants under the Shelf Agreement at September 30, 2025.

At September 30, 2025 and December 31, 2024, the Company had outstanding notes under the Shelf Agreement of $100.0 million.

Principal Maturities of Long-Term Debt

The principal maturities of long-term debt, including interest on finance leases, for the next five years (in thousands) are as follows:


	Amount
2025	$	230
2026		991
2027		—
2028		—
2029		218,000
Thereafter		—
Total		219,221
Less: Amounts Representing Interest on Finance Leases		22
Total	$	219,199

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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+ Details

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Current Assets:
Cash and cash equivalents	$ 35,500	$ 19,473
Accounts receivable, net	365,343	322,991
Prepaid expenses	34,830	35,497
Income tax receivable	48,796	44,107
Other current assets	12,525	13,701
Total current assets	496,994	435,769
Property and Equipment, at cost	4,181,930	3,790,069
Less: accumulated depreciation and amortization	1,368,123	1,233,134
Net property and equipment	2,813,807	2,556,935
Operating Lease Right-of-Use Assets	138,845	126,828
Goodwill and Identifiable Intangibles, net	15,802	16,442
Other Noncurrent Assets	35,512	30,883
Total assets	3,500,960	3,166,857
Current Liabilities:
Accounts payable	112,534	114,560
Wages, vacation and employees’ benefits	72,318	49,953
Claims and insurance accruals	45,437	43,126
Other current liabilities	37,415	38,036
Current portion of long-term debt	1,199	5,313
Current portion of operating lease liability	27,001	27,372
Total current liabilities	295,904	278,360
Other Liabilities:
Long-term debt, less current portion	218,000	194,981
Operating lease liability, less current portion	102,175	96,798
Deferred income taxes	287,123	219,062
Claims, insurance and other	71,731	66,385
Total other liabilities	679,029	577,226
Commitments and Contingencies (Note 3)
Stockholders’ Equity:
Preferred stock, $0.001 par value, 50,000 shares authorized, none issued and outstanding	0	0
Common stock, $0.001 par value, 100,000,000 shares authorized, 26,642,641 and 26,598,512 shares issued and outstanding at September 30, 2025 and December 31, 2024, respectively	27	27
Additional paid-in-capital	303,268	295,106
Deferred compensation trust, 69,573 and 70,100 shares of common stock at cost at September 30, 2025 and December 31, 2024, respectively	(8,904)	(7,981)
Retained earnings	2,231,636	2,024,119
Total stockholders’ equity	2,526,027	2,311,271
Total liabilities and stockholders’ equity	$ 3,500,960	$ 3,166,857

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2025

Accounting Policies [Abstract]

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements include the accounts of Saia, Inc. and its wholly-owned subsidiaries (together, the Company or Saia). All significant intercompany accounts and transactions have been eliminated in the condensed consolidated financial statements.

The condensed consolidated financial statements have been prepared by the Company without audit by the independent registered public accounting firm. In the opinion of management, all normal recurring adjustments necessary for a fair presentation of the condensed consolidated balance sheets, statements of operations, stockholders’ equity and cash flows for the interim periods included herein have been made. These interim condensed consolidated financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles for interim financial information, the instructions to Quarterly Report on Form 10-Q and Rule 10-01 of Regulation S-X. Certain information and note disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles have been condensed or omitted from these statements. The accompanying condensed consolidated financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2024. Operating results for the quarter and nine months ended September 30, 2025 are not necessarily indicative of the results of operations that may be expected for the year ended December 31, 2025.

Business

The Company provides national less-than-truckload (LTL) services through a single integrated organization. While approximately 97 percent of its revenue has been derived from transporting LTL shipments across the contiguous United States, the Company also offers customers a wide range of other value-added services, including non-asset truckload, expedited transportation and logistics services across North America. The Company’s customer base is diversified across numerous industries.

Revenue Recognition

The Company’s revenues are derived primarily from the transportation of freight as it satisfies performance obligations that arise from contracts with its customers. The Company’s performance obligations arise when it receives a bill of lading (BOL) to transport a customer's commodities at negotiated prices contained in either a transportation services agreement or a publicly disclosed tariff rate. Once a BOL is received and accepted, a legally-enforceable contract is formed whereby the parties are committed to perform and the rights of the parties, shipping terms and conditions, and payment terms have been identified. Each shipment represents a distinct service that is a separately identified performance obligation.

The typical transit time to complete a shipment is from one to five days. Billing for transportation services normally occurs after completion of the service and payment is generally due within 30 days after the invoice date. The Company recognizes revenue related to the Company’s LTL, non-asset truckload and expedited transportation services over the transit time of the shipment as it moves from origin to destination based on the transit status at the end of each reporting period.

Key estimates included in the recognition and measurement of revenue and related accounts receivable are as follows:

•

Revenue associated with shipments in transit is recognized ratably over the transit time; and

•

Adjustments to revenue for billing adjustments and collectability.

The portion of the gross invoice related to interline transportation services that involve the services of another party, such as another LTL service provider, is not recorded in the Company’s revenues. Revenue from logistics services is recognized as the services are provided.

Claims and Insurance Accruals

The Company maintains insurance coverage with third-party insurance carriers that provides various levels of protection for covered risk exposure, including in the areas of workers’ compensation, bodily injury and property damage, casualty, cargo loss and damage and group health, with coverage limits and retention and deductible amounts that vary based on policy periods and claim type. Claims and insurance accruals related to workers’ compensation, bodily injury and property damage, casualty, cargo loss and damage and group health are established by management based on estimates of losses that the Company will ultimately incur on reported claims and on claims that have been incurred but not yet reported. Accruals are calculated on reported claims based on an evaluation of the nature and severity of the claim, historical loss experience and on legal, economic and other factors. Actuarial analysis is also used in calculating the accruals for workers’ compensation and bodily injury and property damage claims.

Property and Equipment

Property and equipment are carried at cost less accumulated depreciation. The Company periodically evaluates estimated useful lives of property and equipment considering its planned and actual usage, planned and actual maintenance and replacement, and other relevant physical and economic factors that may affect our use of the assets. During the second quarter of 2024, the Company determined that the estimated useful lives of certain of its trailers and dollies should be extended from 14 years to 20 years. This change is recognized prospectively. The changes in estimates resulted in an increase in income from continuing operations of approximately $2.9 million (a $2.2 million increase in net income) for the nine months ended September 30, 2025.

Segment Reporting

Saia is comprised of a single reportable segment organized around its transportation services. The measure of segment assets is reported on the balance sheet as total consolidated assets.

The following table presents selected financial information with respect to the Company’s single reportable segment (in thousands):


	Third Quarter						Nine Months
	2025			2024			2025			2024
Revenue	$	839,644		$	842,103		$	2,444,334		$	2,420,122
Less:
Wages (a)		235,667			243,407			700,636			678,056
Salaries (a)		50,292			48,914			152,118			140,697
Purchased Transportation		59,329			65,584			176,877			179,138
Other Segment items (b)		311,055			303,911			939,730			883,940
Depreciation and Amortization		64,037			54,656			185,626			156,041
Interest Expense		4,483			2,997			13,510			5,951
Interest Income		(44	)		(45	)		(117	)		(910	)
Income Tax Expense		28,509			29,931			68,437			91,247


Segment and Consolidated Net Income	$	86,316		$	92,748		$	207,517		$	285,962

(a) Wages includes payroll costs for non-management employees generally paid on an hourly or per-mile basis. Salaries includes payroll costs for exempt employees.

(b) Other segment items include employees' benefits, fuel, operating expenses and supplies, operating taxes and licenses and claims and insurance.

- Definition

Disclosure of accounting policy for revenue from contract with customer.

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- Definition

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+ Details

Summary of Significant Accounting Policies - Additional Information1 (Detail) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024
Summary of Significant Accounting Policies [Line Items]
Net income	$ 86,316	$ 71,391	$ 49,810	$ 92,748	$ 102,519	$ 90,695	$ 207,517	$ 285,962
Property and Equipment [Member]
Summary of Significant Accounting Policies [Line Items]
Income loss from continuing operations							2,900
Net income							$ 2,200
Maximum [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2024-07-01
Summary of Significant Accounting Policies [Line Items]
Payment terms	30 days						30 days
Maximum [Member] \| Property and Equipment [Member]
Summary of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	20 years						20 years
Minimum [Member] \| Property and Equipment [Member]
Summary of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	14 years						14 years

- Definition

Amount after tax of income (loss) from continuing operations attributable to the parent.

+ References

+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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-SubTopic 220
-Name Accounting Standards Codification
-Section S99
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+ Details

Summary of Significant Accounting Policies - Schedule of Measure of Segment Assets (Details) - USD ($)
$ in Thousands

3 Months Ended

9 Months Ended

Sep. 30, 2025

Sep. 30, 2024

Sep. 30, 2025

Sep. 30, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Revenues

$ 839,644

$ 842,103

$ 2,444,334

$ 2,420,122

Wages

^[1]

235,667

243,407

700,636

678,056

Salaries

^[1]

50,292

48,914

152,118

140,697

Purchased Transportation

59,329

65,584

176,877

179,138

Other Segment items

^[2]

311,055

303,911

939,730

883,940

Depreciation and amortization

64,037

54,656

185,626

156,041

Interest Expense

4,483

2,997

13,510

5,951

Interest Income

(44)

(45)

(117)

(910)

Income Tax Expense

28,509

29,931

68,437

91,247

Segment and Consolidated Net Income

$ 86,316

$ 92,748

$ 207,517

$ 285,962

[1]	Wages includes payroll costs for non-management employees generally paid on an hourly or per-mile basis. Salaries includes payroll costs for exempt employees.
[2]	Other segment items include employees' benefits, fuel, operating expenses and supplies, operating taxes and licenses and claims and insurance.

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Deferred Compensation Trust [Member]	Retained Earnings [Member]
Beginning Balance at Dec. 31, 2023	$ 1,941,494	$ 27	$ 285,092	$ (5,679)	$ 1,662,054
Beginning Balance, Shares at Dec. 31, 2023		26,549
Stock compensation, including options and long-term incentives	2,724		2,724
Exercise of stock options less shares withheld for taxes	1,993		1,993
Exercise of stock options less shares withheld for taxes, Shares		17
Shares issued for long-term incentive awards, net of shares withheld for taxes, Shares		22
Shares issued for long-term incentive awards, net of shares withheld for taxes	(7,968)		(7,968)
Purchase of shares by Deferred Compensation Trust			314	(314)
Sale of shares by Deferred Compensation Trust			(65)	65
Net Income (Loss)	90,695				90,695
Ending Balance at Mar. 31, 2024	2,028,938	$ 27	282,090	(5,928)	1,752,749
Ending Balance, Shares at Mar. 31, 2024		26,588
Beginning Balance at Dec. 31, 2023	1,941,494	$ 27	285,092	(5,679)	1,662,054
Beginning Balance, Shares at Dec. 31, 2023		26,549
Net Income (Loss)	285,962
Ending Balance at Sep. 30, 2024	2,231,485	$ 27	291,319	(7,877)	1,948,016
Ending Balance, Shares at Sep. 30, 2024		26,595
Beginning Balance at Mar. 31, 2024	2,028,938	$ 27	282,090	(5,928)	1,752,749
Beginning Balance, Shares at Mar. 31, 2024		26,588
Stock compensation, including options and long-term incentives	3,207		3,207
Director deferred share activity , Shares		2
Director deferred share activity	1,422		1,422
Purchase of shares by Deferred Compensation Trust			931	(931)
Sale of shares by Deferred Compensation Trust			(39)	39
Net Income (Loss)	102,519				102,519
Ending Balance at Jun. 30, 2024	2,136,086	$ 27	287,611	(6,820)	1,855,268
Ending Balance, Shares at Jun. 30, 2024		26,590
Stock compensation, including options and long-term incentives	3,463		3,463
Exercise of stock options less shares withheld for taxes	40		40
Shares issued for long-term incentive awards, net of shares withheld for taxes, Shares		5
Shares issued for long-term incentive awards, net of shares withheld for taxes	(852)		(852)
Purchase of shares by Deferred Compensation Trust			1,572	(1,572)
Sale of shares by Deferred Compensation Trust			(515)	515
Net Income (Loss)	92,748				92,748
Ending Balance at Sep. 30, 2024	2,231,485	$ 27	291,319	(7,877)	1,948,016
Ending Balance, Shares at Sep. 30, 2024		26,595
Beginning Balance at Dec. 31, 2024	2,311,271	$ 27	295,106	(7,981)	2,024,119
Beginning Balance, Shares at Dec. 31, 2024		26,599
Stock compensation, including options and long-term incentives	4,527		4,527
Exercise of stock options less shares withheld for taxes	2,463		2,463
Exercise of stock options less shares withheld for taxes, Shares		10
Shares issued for long-term incentive awards, net of shares withheld for taxes, Shares		25
Shares issued for long-term incentive awards, net of shares withheld for taxes	(7,644)		(7,644)
Purchase of shares by Deferred Compensation Trust			1,007	(1,007)
Net Income (Loss)	49,810				49,810
Ending Balance at Mar. 31, 2025	2,360,427	$ 27	295,459	(8,988)	2,073,929
Ending Balance, Shares at Mar. 31, 2025		26,634
Beginning Balance at Dec. 31, 2024	2,311,271	$ 27	295,106	(7,981)	2,024,119
Beginning Balance, Shares at Dec. 31, 2024		26,599
Net Income (Loss)	207,517
Ending Balance at Sep. 30, 2025	2,526,027	$ 27	303,268	(8,904)	2,231,636
Ending Balance, Shares at Sep. 30, 2025		26,643
Beginning Balance at Mar. 31, 2025	2,360,427	$ 27	295,459	(8,988)	2,073,929
Beginning Balance, Shares at Mar. 31, 2025		26,634
Stock compensation, including options and long-term incentives	3,727		3,727
Director deferred share activity , Shares		2
Director deferred share activity	1,077		1,077
Shares issued for long-term incentive awards, net of shares withheld for taxes	(100)		(100)
Purchase of shares by Deferred Compensation Trust			566	(566)
Sale of shares by Deferred Compensation Trust			(136)	136
Net Income (Loss)	71,391				71,391
Ending Balance at Jun. 30, 2025	2,436,522	$ 27	300,593	(9,418)	2,145,320
Ending Balance, Shares at Jun. 30, 2025		26,636
Stock compensation, including options and long-term incentives	3,978		3,978
Shares issued for long-term incentive awards, net of shares withheld for taxes, Shares		7
Shares issued for long-term incentive awards, net of shares withheld for taxes	(789)		(789)
Sale of shares by Deferred Compensation Trust			(514)	514
Net Income (Loss)	86,316				86,316
Ending Balance at Sep. 30, 2025	$ 2,526,027	$ 27	$ 303,268	$ (8,904)	$ 2,231,636
Ending Balance, Shares at Sep. 30, 2025		26,643

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Operating Activities:
Net income	$ 207,517	$ 285,962
Noncash items included in net income:
Depreciation and amortization	185,626	156,041
Deferred income taxes	68,061	6,026
Other, net	6,101	16,276
Changes in operating assets and liabilities:
Accounts receivable	(48,268)	(63,771)
Accounts payable	10,482	12,095
Change in other assets and liabilities, net	28,146	6,334
Net cash provided by operating activities	457,665	418,963
Investing Activities:
Acquisition of property and equipment	(467,814)	(875,302)
Proceeds from disposal of property and equipment	21,736	2,079
Other	(8,394)	4,999
Net cash used in investing activities	(454,472)	(868,224)
Financing Activities:
Repayments of revolving credit facility	(833,000)	(870,100)
Borrowings of revolving credit facility	857,000	953,100
Borrowings on private shelf agreement	0	100,000
Proceeds from stock option exercises	2,463	2,033
Shares withheld for taxes	(8,534)	(8,820)
Repayment of finance leases	(5,095)	(8,525)
Other financing activity	0	(237)
Net cash provided by financing activities	12,834	167,451
Net (Decrease) Increase in Cash and Cash Equivalents	16,027	(281,810)
Cash and Cash Equivalents, beginning of period	19,473	296,215
Cash and Cash Equivalents, end of period	$ 35,500	$ 14,405

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024
Pay vs Performance Disclosure
Net Income (Loss)	$ 86,316	$ 71,391	$ 49,810	$ 92,748	$ 102,519	$ 90,695	$ 207,517	$ 285,962

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2025	Oct. 28, 2025
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2025
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	Q3
Entity Registrant Name	Saia, Inc.
Entity Central Index Key	0001177702
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		26,642,641
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity File Number	0-49983
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	48-1229851
Document Quarterly Report	true
Document Transition Report	false
Entity Address, Address Line One	11465 Johns Creek Parkway
Entity Address, Address Line Two	Suite 400
Entity Address, City or Town	Johns Creek
Entity Address, State or Province	GA
Entity Address, Postal Zip Code	30097
City Area Code	770
Local Phone Number	232-5067
Title of each class	Common Stock, par value $.001 per share
Trading Symbol	SAIA
Security Exchange Name	NASDAQ

Debt and Financing Arrangements - Summary of Reconciliation of Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Dec. 09, 2024
Debt Instrument [Line Items]
Credit Arrangements, described below	$ 218,000	$ 194,000
Finance Leases	1,199	6,294
Total debt	219,199	200,294
Less: current portion of long-term debt	1,199	5,313
Long-term debt, less current portion	$ 218,000	$ 194,981
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	us-gaap:FinanceLeaseLiabilityNoncurrent	us-gaap:FinanceLeaseLiabilityNoncurrent
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit Arrangements, described below	$ 445,600		$ 300,000

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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+ Details

Computation of Earnings Per Share - Summary of Calculation of Basic Earnings Per Common Share and Diluted Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024
Numerator:
Net income	$ 86,316	$ 71,391	$ 49,810	$ 92,748	$ 102,519	$ 90,695	$ 207,517	$ 285,962
Denominator:
Denominator for basic earnings per share-weighted average common shares	26,745			26,695			26,735	26,686
Dilutive effect of share-based awards	45			94			49	99
Denominator for diluted earnings per share-adjusted weighted average common shares	26,790			26,789			26,784	26,785
Basic Earnings Per Share	$ 3.23			$ 3.47			$ 7.76	$ 10.72
Diluted Earnings Per Share	$ 3.22			$ 3.46			$ 7.75	$ 10.68

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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+ Details

- Definition

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-Paragraph 9
-Subparagraph (e)
-Publisher FASB
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-Subparagraph (d)(1)
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-Publisher FASB
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-URI https://asc.fasb.org/1943274/2147481538/470-20-65-4

+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Condensed Consolidated Statements of Operations (unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Income Statement [Abstract]
Operating Revenue	$ 839,644	$ 842,103	$ 2,444,334	$ 2,420,122
Operating Expenses:
Salaries, wages and employees' benefits	401,058	398,134	1,181,289	1,112,087
Purchased transportation	59,329	65,584	176,877	179,138
Fuel, operating expenses and supplies	165,727	158,733	494,032	475,935
Operating taxes and licenses	20,867	19,942	63,318	59,401
Claims and insurance	23,614	19,274	67,985	55,565
Depreciation and amortization	64,037	54,656	185,626	156,041
Other operating, net	(13,598)	609	(12,970)	1,279
Total operating expenses	721,034	716,932	2,156,157	2,039,446
Operating Income	118,610	125,171	288,177	380,676
Nonoperating (Income) Expenses:
Interest expense	4,483	2,997	13,510	5,951
Interest income	(44)	(45)	(117)	(910)
Other, net	(654)	(460)	(1,170)	(1,574)
Nonoperating expenses, net	3,785	2,492	12,223	3,467
Income Before Income Taxes	114,825	122,679	275,954	377,209
Income Tax Provision	28,509	29,931	68,437	91,247
Net Income	$ 86,316	$ 92,748	$ 207,517	$ 285,962
Weighted average common shares outstanding - basic	26,745	26,695	26,735	26,686
Weighted average common shares outstanding - diluted	26,790	26,789	26,784	26,785
Basic Earnings Per Share	$ 3.23	$ 3.47	$ 7.76	$ 10.72
Diluted Earnings Per Share	$ 3.22	$ 3.46	$ 7.75	$ 10.68

Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2025

Accounting Policies [Abstract]

Schedule of Measure of Segment Assets

The following table presents selected financial information with respect to the Company’s single reportable segment (in thousands):


	Third Quarter						Nine Months
	2025			2024			2025			2024
Revenue	$	839,644		$	842,103		$	2,444,334		$	2,420,122
Less:
Wages (a)		235,667			243,407			700,636			678,056
Salaries (a)		50,292			48,914			152,118			140,697
Purchased Transportation		59,329			65,584			176,877			179,138
Other Segment items (b)		311,055			303,911			939,730			883,940
Depreciation and Amortization		64,037			54,656			185,626			156,041
Interest Expense		4,483			2,997			13,510			5,951
Interest Income		(44	)		(45	)		(117	)		(910	)
Income Tax Expense		28,509			29,931			68,437			91,247


Segment and Consolidated Net Income	$	86,316		$	92,748		$	207,517		$	285,962

(a) Wages includes payroll costs for non-management employees generally paid on an hourly or per-mile basis. Salaries includes payroll costs for exempt employees.

(b) Other segment items include employees' benefits, fuel, operating expenses and supplies, operating taxes and licenses and claims and insurance.

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2025

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

(1) Summary of Significant Accounting Policies

Basis of Presentation

Business

Revenue Recognition

Key estimates included in the recognition and measurement of revenue and related accounts receivable are as follows:

•

Revenue associated with shipments in transit is recognized ratably over the transit time; and

•

Adjustments to revenue for billing adjustments and collectability.

Claims and Insurance Accruals

Property and Equipment

Segment Reporting

Saia is comprised of a single reportable segment organized around its transportation services. The measure of segment assets is reported on the balance sheet as total consolidated assets.

The following table presents selected financial information with respect to the Company’s single reportable segment (in thousands):


	Third Quarter						Nine Months
	2025			2024			2025			2024
Revenue	$	839,644		$	842,103		$	2,444,334		$	2,420,122
Less:
Wages (a)		235,667			243,407			700,636			678,056
Salaries (a)		50,292			48,914			152,118			140,697
Purchased Transportation		59,329			65,584			176,877			179,138
Other Segment items (b)		311,055			303,911			939,730			883,940
Depreciation and Amortization		64,037			54,656			185,626			156,041
Interest Expense		4,483			2,997			13,510			5,951
Interest Income		(44	)		(45	)		(117	)		(910	)
Income Tax Expense		28,509			29,931			68,437			91,247


Segment and Consolidated Net Income	$	86,316		$	92,748		$	207,517		$	285,962

(a) Wages includes payroll costs for non-management employees generally paid on an hourly or per-mile basis. Salaries includes payroll costs for exempt employees.

(b) Other segment items include employees' benefits, fuel, operating expenses and supplies, operating taxes and licenses and claims and insurance.

Debt and Financing Arrangements - Additional Information (Detail) - USD ($) $ in Thousands				9 Months Ended
	Dec. 09, 2024	May 01, 2024	Nov. 09, 2023	Sep. 30, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Maximum leverage ratio				3.50%
Borrowing capacity under credit agreement				$ 218,000	$ 194,000
Initial Notes interest rate		6.09%
Minimum [Member]
Debt Instrument [Line Items]
Letter of credit unused portion fee	0.175%
Maximum [Member]
Debt Instrument [Line Items]
Letter of credit unused portion fee	0.30%
Base Rate Margin [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Rate margin	0.25%
Base Rate Margin [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Rate margin	1.00%
Secured Overnight Financing Rate [Member]
Debt Instrument [Line Items]
Rate margin	0.10%
Secured Overnight Financing Rate [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Rate margin	1.25%
Secured Overnight Financing Rate [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Rate margin	2.00%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit agreement	$ 600,000
Borrowing capacity under credit agreement	300,000			$ 445,600
Adjusted Leverage Ratio				3.50%
Revolving Credit Facility [Member] \| Existing Credit Agreement [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit agreement				$ 118,000	94,000
Letter of credit facility outstanding amount				36,400	32,200
Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit agreement	150,000
Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit agreement	$ 300,000
Shelf Agreement [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit agreement				$ 100,000	$ 100,000
Private Shelf Agreement [Member]
Debt Instrument [Line Items]
Uncommitted Private Shelf Agreement			$ 350,000
Private Shelf Agreement [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Selling of aggregate principal amount		$ 100,000

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Sep. 30, 2025	Dec. 31, 2024
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	50,000	50,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	26,642,641	26,598,512
Common stock, shares outstanding	26,642,641	26,598,512
Deferred compensation trust	69,573	70,100

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Sep. 30, 2025
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Summary of Significant Accounting Policies - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2025
Minimum [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of revenue derived from transporting	97.00%
Average transit time	1 day
Maximum [Member]
Summary of Significant Accounting Policies [Line Items]
Average transit time	5 days

Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Fair Value Disclosures [Abstract]
Estimated fair value of total debt	$ 220,000	$ 200,500
Total debt	$ 219,199	$ 200,294

Debt and Financing Arrangements - Schedule of Principal Maturities of Long-Term Debt Including Interest On Finance Leases (Detail) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Debt Instruments [Abstract]
2025	$ 230
2026	991
2027	0
2028	0
2029	218,000
Thereafter	0
Total	219,221
Less: Amounts Representing Interest on Finance Leases	22
Total	$ 219,199	$ 200,294