ICF International (ICFI) 10-Q 1 Nov 24 2024 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2024	Oct. 25, 2024
Cover [Abstract]
Entity Registrant Name	ICF International, Inc.
Entity Central Index Key	0001362004
Trading Symbol	ICFI
Security Exchange Name	NASDAQ
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		18,762,710
Document Type	10-Q
Document Period End Date	Sep. 30, 2024
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	001-33045
Entity Tax Identification Number	22-3661438
Entity Incorporation State Country Code	DE
Entity Address, Address Line One	1902 Reston Metro Plaza
Entity Address, City or Town	Reston
Entity Address, State or Province	VA
Entity Address, Postal Zip Code	20190
City Area Code	703
Local Phone Number	934-3000
Title of each class	Common Stock
Entity Interactive Data Current	Yes
Document Quarterly Report	true
Document Transition Report	false

CONSOLIDATED BALANCE SHEETS (UN

CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Current Assets:
Cash and cash equivalents	$ 6,911	$ 6,361
Restricted cash	724	3,088
Contract receivables, net	212,412	205,484
Contract assets	237,742	201,832
Prepaid expenses and other assets	24,785	28,055
Income tax receivable	10,541	2,337
Total Current Assets	493,115	447,157
Property and Equipment, net	71,299	75,948
Other Assets:
Goodwill	1,221,437	1,219,476
Other intangible assets, net	70,030	94,904
Operating lease - right-of-use assets	122,543	132,807
Other assets	49,754	41,480
Total Assets	2,028,178	2,011,772
Current Liabilities:
Current portion of long-term debt	13,750	26,000
Accounts payable	121,093	134,503
Contract liabilities	17,176	21,997
Operating lease liabilities	21,204	20,409
Finance lease liabilities	2,590	2,522
Accrued salaries and benefits	91,103	88,021
Accrued subcontractors and other direct costs	55,600	45,645
Accrued expenses and other current liabilities	85,274	79,129
Total Current Liabilities	407,790	418,226
Long-term Liabilities:
Long-term debt	405,396	404,407
Operating lease liabilities - non-current	160,926	175,460
Finance lease liabilities - non-current	11,922	13,874
Deferred income taxes	5,982	26,175
Other long-term liabilities	59,845	56,045
Total Liabilities	1,051,861	1,094,187
Commitments and Contingencies (Note 13)
Stockholders’ Equity:
Preferred stock, par value $.001; 5,000,000 shares authorized; none issued
Common stock, par value $.001; 70,000,000 shares authorized; 24,138,735 and 23,982,132 shares issued at September 30, 2024 and December 31, 2023, respectively; 18,762,710 and 18,845,521 shares outstanding at September 30, 2024 and December 31, 2023, respectively	24	24
Additional paid-in capital	436,671	421,502
Retained earnings	852,835	775,099
Treasury stock, 5,376,025 and 5,136,611 shares at September 30, 2024 and December 31, 2023, respectively	(300,718)	(267,155)
Accumulated other comprehensive loss	(12,495)	(11,885)
Total Stockholders’ Equity	976,317	917,585
Total Liabilities and Stockholders’ Equity	$ 2,028,178	$ 2,011,772

CONSOLIDATED BALANCE SHEETS (_2

CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical) - $ / shares	Sep. 30, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	70,000,000	70,000,000
Common stock, issued (in shares)	24,138,735	23,982,132
Common stock, outstanding (in shares)	18,762,710	18,845,521
Treasury stock, shares (in shares)	5,376,025	5,136,611

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Statement [Abstract]
Revenue	$ 516,998	$ 501,519	$ 1,523,463	$ 1,484,886
Direct costs:
Direct costs	325,047	323,504	964,911	961,473
Operating costs and expenses:
Indirect and selling expenses	132,816	131,553	389,001	381,808
Depreciation and amortization	4,820	5,917	15,303	19,052
Amortization of intangible assets	8,291	8,644	24,873	27,154
Total operating costs and expenses	145,927	146,114	429,177	428,014
Operating income	46,024	31,901	129,375	95,399
Interest, net	(7,195)	(10,557)	(23,136)	(30,146)
Other (expense) income	(899)	2,736	767	1,501
Income before income taxes	37,930	24,080	107,006	66,754
Provision for income taxes	5,251	340	21,399	6,304
Net income	$ 32,679	$ 23,740	$ 85,607	$ 60,450
Earnings per Share:
Basic	$ 1.74	$ 1.26	$ 4.57	$ 3.22
Diluted	$ 1.73	$ 1.25	$ 4.53	$ 3.19
Weighted-average Shares:
Basic	18,760	18,815	18,752	18,795
Diluted	18,910	18,974	18,915	18,958
Cash dividends declared per common share	$ 0.14	$ 0.14	$ 0.42	$ 0.42
Other comprehensive loss, net of tax	$ (951)	$ (4,053)	$ (610)	$ (2,236)
Comprehensive income, net of tax	$ 31,728	$ 19,687	$ 84,997	$ 58,214

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Loss
Balance at Dec. 31, 2022	$ 853,211	$ 23	$ 401,957	$ 703,030	$ (243,666)	$ (8,133)
Balance (in shares) at Dec. 31, 2022		18,883			4,906
Net Income (Loss)	16,398			16,398
Other comprehensive (loss) income	(1,334)					(1,334)
Equity compensation	3,750		3,750
Exercise of stock options	111		111
Exercise of stock options (in shares)		4
Issuance of shares pursuant to employee stock purchase plan and vesting of restricted stock units	1	$ 1
Issuance of shares pursuant to employee stock purchase plan and vesting of restricted stock units (in shares)		126
Payments for share repurchases	(22,815)				$ (22,815)
Payments for share repurchases (in shares)		(225)			225
Dividends declared	(2,633)			(2,633)
Balance at Mar. 31, 2023	846,689	$ 24	405,818	716,795	$ (266,481)	(9,467)
Balance (in shares) at Mar. 31, 2023		18,788			5,131
Balance at Dec. 31, 2022	853,211	$ 23	401,957	703,030	$ (243,666)	(8,133)
Balance (in shares) at Dec. 31, 2022		18,883			4,906
Net Income (Loss)	60,450
Other comprehensive (loss) income	(2,236)					(2,236)
Balance at Sep. 30, 2023	893,330	$ 24	414,633	755,572	$ (266,530)	(10,369)
Balance (in shares) at Sep. 30, 2023		18,817			5,131
Balance at Mar. 31, 2023	846,689	$ 24	405,818	716,795	$ (266,481)	(9,467)
Balance (in shares) at Mar. 31, 2023		18,788			5,131
Net Income (Loss)	20,312			20,312
Other comprehensive (loss) income	3,151					3,151
Equity compensation	2,938		2,938
Exercise of stock options	167		167
Exercise of stock options (in shares)		4
Issuance of shares pursuant to employee stock purchase plan and vesting of restricted stock units	2,264	$ 0	2,264
Issuance of shares pursuant to employee stock purchase plan and vesting of restricted stock units (in shares)		23
Payments for share repurchases	(37)				$ (37)
Dividends declared	(2,639)			(2,639)
Balance at Jun. 30, 2023	872,845	$ 24	411,187	734,468	$ (266,518)	(6,316)
Balance (in shares) at Jun. 30, 2023		18,815			5,131
Net Income (Loss)	23,740			23,740
Other comprehensive (loss) income	(4,053)					(4,053)
Equity compensation	3,446		3,446
Issuance of shares pursuant to employee stock purchase plan and vesting of restricted stock units (in shares)		2
Payments for share repurchases	(12)				$ (12)
Dividends declared	(2,636)			(2,636)
Balance at Sep. 30, 2023	893,330	$ 24	414,633	755,572	$ (266,530)	(10,369)
Balance (in shares) at Sep. 30, 2023		18,817			5,131
Balance at Dec. 31, 2023	917,585	$ 24	421,502	775,099	$ (267,155)	(11,885)
Balance (in shares) at Dec. 31, 2023		18,846			5,136
Net Income (Loss)	27,317			27,317
Other comprehensive (loss) income	684					684
Equity compensation	3,551		3,551
Exercise of stock options	107		107
Exercise of stock options (in shares)		2
Issuance of shares pursuant to employee stock purchase plan and vesting of restricted stock units (in shares)		125
Payments for share repurchases	(30,475)				$ (30,475)
Payments for share repurchases (in shares)		(218)			218
Dividends declared	(2,620)			(2,620)
Balance at Mar. 31, 2024	916,149	$ 24	425,160	799,796	$ (297,630)	(11,201)
Balance (in shares) at Mar. 31, 2024		18,755			5,354
Balance at Dec. 31, 2023	917,585	$ 24	421,502	775,099	$ (267,155)	(11,885)
Balance (in shares) at Dec. 31, 2023		18,846			5,136
Net Income (Loss)	85,607
Other comprehensive (loss) income	(610)					(610)
Balance at Sep. 30, 2024	976,317	$ 24	436,671	852,835	$ (300,718)	(12,495)
Balance (in shares) at Sep. 30, 2024		18,762			5,376
Balance at Mar. 31, 2024	916,149	$ 24	425,160	799,796	$ (297,630)	(11,201)
Balance (in shares) at Mar. 31, 2024		18,755			5,354
Net Income (Loss)	25,611			25,611
Other comprehensive (loss) income	(343)					(343)
Equity compensation	4,674		4,674
Issuance of shares pursuant to employee stock purchase plan and vesting of restricted stock units	2,568		2,568
Issuance of shares pursuant to employee stock purchase plan and vesting of restricted stock units (in shares)		21
Payments for share repurchases	(2,711)				$ (2,711)
Payments for share repurchases (in shares)		(19)			19
Dividends declared	(2,623)			(2,623)
Balance at Jun. 30, 2024	943,325	$ 24	432,402	822,784	$ (300,341)	(11,544)
Balance (in shares) at Jun. 30, 2024		18,757			5,373
Net Income (Loss)	32,679			32,679
Other comprehensive (loss) income	(951)					(951)
Equity compensation	4,269		4,269
Issuance of shares pursuant to employee stock purchase plan and vesting of restricted stock units (in shares)		8
Payments for share repurchases	(377)				$ (377)
Payments for share repurchases (in shares)		(3)			3
Dividends declared	(2,628)			(2,628)
Balance at Sep. 30, 2024	$ 976,317	$ 24	$ 436,671	$ 852,835	$ (300,718)	$ (12,495)
Balance (in shares) at Sep. 30, 2024		18,762			5,376

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Cash Flows from Operating Activities
Net income	$ 85,607	$ 60,450
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	3,176	691
Deferred income taxes and unrecognized income tax benefits	(16,957)	(3,533)
Non-cash equity compensation	12,494	10,134
Depreciation and amortization	40,177	46,207
Gain on divestiture of a business	(2,009)	(4,302)
Other operating adjustments, net	2,206	2,563
Changes in operating assets and liabilities, net of the effects of acquisitions:
Net contract assets and liabilities	(40,155)	(52,010)
Contract receivables	(9,634)	12,087
Prepaid expenses and other assets	(434)	11,893
Operating lease assets and liabilities, net	(3,065)	3,897
Accounts payable	(13,402)	(13,333)
Accrued salaries and benefits	2,889	(8,521)
Accrued subcontractors and other direct costs	9,660	(3,353)
Accrued expenses and other current liabilities	16,979	(18,727)
Income tax receivable and payable	(9,574)	450
Other liabilities	(1,774)	959
Net Cash Provided by Operating Activities	76,184	45,552
Cash Flows from Investing Activities
Payments for purchase of property and equipment and capitalized software	(15,559)	(17,876)
Payments for business acquisitions, net of cash acquired		(32,664)
Proceeds from divestiture of a business	1,985	47,151
Net Cash Used in Investing Activities	(13,574)	(3,389)
Cash Flows from Financing Activities
Advances from working capital facilities	917,953	972,266
Payments on working capital facilities	(930,043)	(995,244)
Proceeds from other short-term borrowings	43,735	25,394
Repayments of other short-term borrowings	(53,280)	(18,845)
Receipt of restricted contract funds	1,275	6,412
Payment of restricted contract funds	(3,586)	(7,042)
Dividends paid	(7,880)	(7,903)
Net payments for stock issuances and share repurchases	(30,995)	(20,601)
Other financing, net	(1,777)	(1,501)
Net Cash Used in Financing Activities	(64,598)	(47,064)
Effect of Exchange Rate Changes on Cash, Cash Equivalents, and Restricted Cash	174	(213)
Decrease in Cash, Cash Equivalents, and Restricted Cash	(1,814)	(5,114)
Cash, Cash Equivalents, and Restricted Cash, Beginning of Period	9,449	12,968
Cash, Cash Equivalents, and Restricted Cash, End of Period	7,635	7,854
Supplemental Disclosure of Cash Flow Information
Interest	24,388	29,173
Income taxes	$ 50,382	$ 12,604

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ 32,679	$ 25,611	$ 27,317	$ 23,740	$ 20,312	$ 16,398	$ 85,607	$ 60,450

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Sep. 30, 2024
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

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	NOTE 1 – BASIS OF PRESENTATION Basis of Presentation The accompanying consolidated financial statements are of ICF International, Inc. (“ICFI”) and its principal subsidiary, ICF Consulting Group, Inc. (“Consulting,” and together with ICFI, the “Company”), and have been prepared in accordance with United States (“U.S.”) generally accepted accounting principles (“U.S. GAAP”). Consulting is a wholly owned subsidiary of ICFI. ICFI is a holding company with no operations or assets other than its investment in the common stock of Consulting. All other subsidiaries of the Company are wholly owned by Consulting. Intercompany transactions and balances have been eliminated. The terms “federal” or “federal government” refer to the U.S. federal government, and “state and local” or “state and local government” refer to U.S. state (including territories) and local governments, unless otherwise indicated. Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities, and the reported amounts of revenue and expenses. Key estimates include estimates related to variable consideration on contracts with customers, costs to complete fixed-price contracts, bonus and other incentive compensation, reserves for tax benefits and valuation allowances on deferred tax assets, collectability of receivables, valuation and useful lives of acquired tangible and intangible assets, impairment of goodwill and long-lived assets, and contingencies. Actual results experienced by the Company may differ from management’s estimates. Interim Results The unaudited consolidated financial statements included in this Quarterly Report on Form 10-Q have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). These rules and regulations permit some of the information and footnote disclosures normally included in annual financial statements, prepared in accordance with U.S. GAAP, to be condensed or omitted. In management’s opinion, the unaudited consolidated financial statements contain all adjustments that are of a normal recurring nature, necessary for a fair presentation of the results of operations and financial position of the Company for the interim periods presented. The Company reports operating results and financial data in one operating segment and reporting unit. Operating results for the three-month and the nine-month periods ended September 30, 2024 and 2023 are not necessarily indicative of the results that may be expected for the full year. These unaudited consolidated financial statements should be read in conjunction with the audited consolidated financial statements for the fiscal year ended December 31, 2023 and the notes thereto included in the Company’s Annual Report on Form 10-K. Recent Accounting Pronouncements Recent Accounting Pronouncements Not Yet Adopted Segment Reporting In November 2023, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) 2023-07: Improvements to Reportable Segment Disclosures to update reportable segment disclosure requirements for public entities under the Accounting Standards Codification (“ASC”). ASU 2023-07 enhances the current segment reporting disclosures of Topic 280 by requiring disclosure of significant segment expenses that are regularly reviewed by the Chief Operating Decision Maker (the “CODM”), the amount and description of other segment items, and interim disclosures of each reportable segment’s profit or loss and assets. ASU 2023-07 also requires public entities that have a single reportable segment to provide all of the disclosures required in Topic 280, as amended. ASU 2023-07 is effective for the Company for the fiscal year ending December 31, 2024 and interim periods within the 2025 fiscal year on a retrospective basis, with early adoption permitted. The Company expects to adopt the amendments of ASU 2023-07 for the fiscal year ending December 31, 2024, but does not expect the adoption to have a material impact, if any, on the consolidated financial statements. Income Taxes In December 2023, the FASB issued ASU 2023-09, Income Taxes: Improvements to Income Tax Disclosures, which requires greater disaggregation of income tax rates and amounts paid by entities. ASU 2023-09 specifically requires all entities to disclose, on an annual basis, disaggregated domestic and foreign pre-tax income or loss from continuing operations and the disaggregated income tax expense or benefit by federal, state, and foreign components, and a tabular rate reconciliation, using both percentages and reporting currency amounts, of eight specific categories as well as any individual reconciling items that are equal to or greater than 5% of a threshold computed by multiplying pretax income or loss from continuing operations by the applicable federal rate. Additionally, the amendments also require disclosure of income taxes paid disaggregated by federal, state, and foreign jurisdictions as well as any individual jurisdictions over 5% of the total income taxes paid. ASU 2023-09 is effective for the Company for the fiscal year ending December 31, 2025, with early adoption permitted. The amendments may be adopted on a prospective or retrospective basis. The Company is currently evaluating the impact of the adoption of ASU 2023-09 but does not expect the adoption to have a material impact, if any, on the consolidated financial statements.

Restricted Cash

Restricted Cash	9 Months Ended
	Sep. 30, 2024
Cash and Cash Equivalents [Abstract]
Restricted Cash	NOTE 2 – RESTRICTED CASH The following table provides a reconciliation of cash and cash equivalents and restricted cash reported within the consolidated balance sheets for the periods presented to the total of cash, cash equivalents, and restricted cash shown in the consolidated statements of cash flows for the nine months ended September 30, 2024 and 2023: September 30, 2024 September 30, 2023 Beginning Ending Beginning Ending Cash and cash equivalents $ 6,361 $ 6,911 $ 11,257 $ 5,084 Restricted cash 3,088 724 1,711 2,770 Total of cash, cash equivalents, and restricted cash shown in the consolidated statements of cash flows $ 9,449 $ 7,635 $ 12,968 $ 7,854

Contract Receivables, Net

Contract Receivables, Net	9 Months Ended
	Sep. 30, 2024
Receivables [Abstract]
Contract Receivables, Net	NOTE 3 – CONTRACT RECEIVABLES, NET Contract receivables, net consisted of the following: September 30, 2024 December 31, 2023 Billed and billable $ 220,690 $ 210,919 Allowance for expected credit losses ( 8,278 ) ( 5,435 ) Contract receivables, net $ 212,412 $ 205,484 The Company sells certain billed contract receivables in accordance with its Master Receivables Purchase Agreement (the “MRPA”) with MUFG Bank, Ltd. (“MUFG”). The contract receivables that are sold without recourse and where the Company does not retain any ongoing financial interest in the transferred receivables, other than providing servicing activities, are accounted for as sales under ASC 860, Transfers and Servicing (“ASC 860”). Consequently, these contract receivables are derecognized from the Company’s consolidated balance sheets at the date of the sale, and the cash received from MUFG is presented as part of cash flows from operating activities. The following is a reconciliation of billed contract receivables sold to MUFG that were eligible and accounted for as sales under ASC 860, including billed contract receivables sold to MUFG and collected from customers on behalf of MUFG during the nine months ended September 30, 2024 and 2023, and the balance of billed contract receivables not yet collected from customers as of September 30, 2024 and 2023, respectively: As of and for the Nine Months Ended September 30, 2024 September 30, 2023 Beginning balance, billed contract receivables sold and not yet collected (1) $ 21,302 $ 3,819 Billed contract receivables sold during the period (2) 482,469 159,480 Collections from customers during the period (2) ( 473,037 ) ( 131,580 ) Ending balance, billed contract receivables sold and not yet collected (3) $ 30,735 $ 31,719 (1) The beginning balances represent billed contract receivables that were previously sold and derecognized by the Company but have not yet been collected from customers as of January 1, 2024 and 2023 , respectively. (2) For the nine months ended September 30, 2024 and 2023, the Company recorded net inflows of $ 9.4 million and $ 27.9 million , respectively, in its cash flows from operating activities from the sale of billed contract receivables. (3) The ending balances represent billed contract receivables that were sold and derecognized by the Company but have not yet been collected from customers as of September 30, 2024 and 2023 , respectively. The following is a reconciliation of cash collections from customers of billed contract receivables previously sold to MUFG that were eligible and accounted for as sales under ASC 860, including collections from customers on behalf of MUFG of previously sold billed contract receivables and remittances of cash collections to MUFG during the nine months ended September 30, 2024 and 2023, and the balance of cash collected but not yet remitted to MUFG as of September 30, 2024 and 2023, respectively: As of and for the Nine Months Ended September 30, 2024 September 30, 2023 Beginning balance, cash collected but not yet remitted to MUFG (1) $ 21,796 $ 6,164 Collections from customers during the period (2) 473,037 131,580 Remittances to MUFG during the period (2) ( 463,558 ) ( 127,303 ) Ending balance, cash collected but not yet remitted to MUFG (3) $ 31,275 $ 10,441 (1) The beginning balances represent cash collected from customers on behalf of MUFG for billed contract receivables that were previously sold and derecognized by the Company but have not yet been remitted to MUFG as of January 1, 2024 and 2023 , respectively. (2) For the nine months ended September 30, 2024 and 2023, the Company recorded net inflows of $ 9.5 million and $ 4.3 million , respectively, in its cash flows from operating activities from the collection of billed contract receivables that were sold but not yet remitted to MUFG. (3) The ending balances are included as part of “Accrued expenses and other current liabilities” on the Company’s consolidated balance sheets. The Company services the receivables sold by collecting cash and remitting it to MUFG. The related servicing fee received from MUFG was immaterial. The aggregate impact of the sale of billed contract receivables on the Company’s operating cash flows was $ 18.9 million and $ 32.2 million for the nine months ended September 30, 2024 and 2023, respectively. The Company also sold certain billed contract receivables to MUFG that did not qualify as sales under ASC 860. Consequently, the cash received from and remitted back to MUFG is presented as cash from financing activities within “Proceeds from other short-term borrowings” and “Repayments of other short-term borrowings” on the Company’s consolidated statements of cash flows. At September 30, 2024 and December 31, 2023, the amounts due to MUFG for cash collected and not yet remitted for billed contract receivables sold that did not qualify as sales under ASC 860 totaled $ 2.7 million and $ 6.9 million , respectively. These amounts are included as part of “Accrued expenses and other current liabilities” on the Company’s consolidated balance sheets.

Leases

Leases	9 Months Ended
	Sep. 30, 2024
Leases [Abstract]
Leases	NOTE 4 – LEASES At September 30, 2024 , the Company had operating and finance leases for facilities and equipment with remaining terms ranging from 1 to 14 years . Future minimum lease payments under non-cancellable operating and finance leases as of September 30, 2024 were as follows: Operating Finance September 30, 2025 $ 27,037 $ 3,041 September 30, 2026 23,268 3,041 September 30, 2027 20,171 3,041 September 29, 2028 16,515 3,004 September 30, 2029 14,065 2,967 Thereafter 121,325 741 Total future minimum lease payments 222,381 15,835 Less: Interest ( 40,251 ) ( 1,323 ) Total lease liabilities $ 182,130 $ 14,512 Lease liabilities - current $ 21,204 $ 2,590 Lease liabilities - non-current 160,926 11,922 Total lease liabilities $ 182,130 $ 14,512

Debt

Debt	9 Months Ended
	Sep. 30, 2024
Debt Disclosure [Abstract]
Debt	NOTE 5 – DEBT At September 30, 2024 and December 31, 2023, debt consisted of: September 30, 2024 December 31, 2023 Average Outstanding Average Outstanding Term Loan $ 200,250 $ 207,750 Delayed-Draw Term Loan 211,750 220,000 Revolving Credit 10,000 6,340 Total before debt issuance costs 6.8 % 422,000 6.7 % 434,090 Unamortized debt issuance costs ( 2,854 ) ( 3,683 ) Total $ 419,146 $ 430,407 September 30, 2024 December 31, 2023 Current portion of long-term debt $ 13,750 $ 26,000 Long-term debt - non-current 405,396 404,407 Total $ 419,146 $ 430,407 As of September 30, 2024, the Company had $ 588.2 million of unused borrowing capacity under the $ 600.0 million revolving line of credit under a credit agreement with a group of lenders (the “Credit Facility”). The unused borrowing capacity is inclusive of outstanding letters of credit totaling $ 1.8 million . The average interest rate on borrowings under the Credit Facility was 6.8 % for the nine months ended September 30, 2024 and 6.7 % for the twelve months ended December 31, 2023, respectively. Inclusive of the impact of floating-to-fixed interest rate swaps (see “Note 7 – Derivative Instruments and Hedging Activities”), the average interest rate was 5.4 % for the nine months ended September 30, 2024 and 5.6 % for the twelve months ended December 31, 2023, respectively. Future contractual repayments of debt principal are as follows: Payments due by Term Loan Delayed-Draw Term Loan Revolving Credit Total September 30, 2025 $ — $ 13,750 $ — $ 13,750 September 30, 2026 — 16,500 — 16,500 May 6, 2027 (Maturity) 200,250 181,500 10,000 391,750 Total $ 200,250 $ 211,750 $ 10,000 $ 422,000

Revenue Recognition

Revenue Recognition	9 Months Ended
	Sep. 30, 2024
Revenue from Contract with Customer [Abstract]
Revenue Recognition	NOTE 6 – REVENUE RECOGNITION Disaggregation of Revenue The Company disaggregates revenue from clients into categories that depict how the nature, amount, and uncertainty of revenue and cash flows are affected by economic and business factors. Those categories are client market, client type, and contract mix. Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Dollars Percent Dollars Percent Dollars Percent Dollars Percent Client Markets: Energy, environment, infrastructure, and disaster recovery $ 236,039 46 % $ 204,740 41 % $ 693,229 46 % $ 595,769 40 % Health and social programs 196,586 38 % 209,760 42 % 582,191 38 % 617,997 42 % Security and other civilian & commercial 84,373 16 % 87,019 17 % 248,043 16 % 271,120 18 % Total $ 516,998 100 % $ 501,519 100 % $ 1,523,463 100 % $ 1,484,886 100 % Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Dollars Percent Dollars Percent Dollars Percent Dollars Percent Client Type: U.S. federal government $ 282,022 55 % $ 279,314 56 % $ 829,688 55 % $ 820,116 55 % U.S. state and local government 78,883 15 % 76,594 15 % 240,685 16 % 233,264 16 % International government 26,871 5 % 27,547 5 % 80,831 5 % 74,378 5 % Total Government 387,776 75 % 383,455 76 % 1,151,204 76 % 1,127,758 76 % Commercial 129,222 25 % 118,064 24 % 372,259 24 % 357,128 24 % Total $ 516,998 100 % $ 501,519 100 % $ 1,523,463 100 % $ 1,484,886 100 % Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Dollars Percent Dollars Percent Dollars Percent Dollars Percent Contract Mix: Time-and-materials $ 220,564 43 % $ 206,622 41 % $ 644,822 42 % $ 615,902 41 % Fixed-price 236,538 46 % 223,338 45 % 696,211 46 % 667,982 45 % Cost-based 59,896 11 % 71,559 14 % 182,430 12 % 201,002 14 % Total $ 516,998 100 % $ 501,519 100 % $ 1,523,463 100 % $ 1,484,886 100 % Contract Assets and Liabilities Contract assets consist of unbilled receivables on contracts where revenue recognized exceeds the amount billed. Contract liabilities result from advance payments received on a contract or from billings in excess of revenue recognized. The following table summarizes the contract assets and liabilities as of September 30, 2024 and December 31, 2023: September 30, 2024 December 31, 2023 Contract assets $ 237,742 $ 201,832 Contract liabilities ( 17,176 ) ( 21,997 ) Net contract assets (liabilities) $ 220,566 $ 179,835 The increase in net contract assets (liabilities) is primarily due to the timing difference between the performance of services and billings to customers. During the nine months ended September 30, 2024 and 2023, the Company recognized $ 17.1 million and $ 17.3 million in revenue related to the contract liabilities balance at December 31, 2023 and 2022, respectively. Unfulfilled Performance Obligations The Company had $ 1.4 billion in unfulfilled performance obligations (“UPO”) as of September 30, 2024. The Company expects to recognize the remaining UPO as revenue of approximately 8 % by December 31, 2024 , 65 % by December 31, 2025 , and the remainder thereafter.

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	9 Months Ended
	Sep. 30, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	NOTE 7 – DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES At September 30, 2024 , the Company had floating-to-fixed interest rate swap agreements for an aggregate notional amount of $ 275.0 million, of which $ 100.0 million will mature on February 28, 2025 , $ 75.0 million will mature on February 28, 2028 , and $ 100.0 million will mature on June 27, 2028 . The Company has designated the swap agreements as cash flow hedges. See “Note 5 – Debt” for details on the impact of the swap agreements on the Company’s interest rates. See “Note 12 – Fair Value” for the fair value of these swaps.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2024
Income Tax Disclosure [Abstract]
Income Taxes	NOTE 8 – INCOME TAXES A r econciliation of the Company’s statutory rate to the effective tax rate for the three and nine months ended September 30, 2024 and 2023 is as follows: Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Statutory tax rate 21.0 % 21.0 % 21.0 % 21.0 % State taxes, net of federal benefit 6.0 % 5.8 % 6.0 % 5.8 % Executive compensation 1.6 % 1.4 % 1.6 % 1.4 % Corporate-owned life insurance ( 0.5 %) ( 0.2 %) ( 0.5 %) ( 0.2 %) Other permanent differences 0.4 % 0.4 % 0.4 % 0.3 % Prior year tax adjustments ( 11.0 %) ( 27.1 %) ( 3.7 %) ( 10.8 %) Worthless stock — ( 20.2 %) — ( 7.3 %) Capital loss — — — ( 6.7 %) Valuation allowance 0.9 % 3.1 % 1.0 % 1.9 % Equity-based compensation ( 0.3 %) ( 0.6 %) ( 1.7 %) ( 1.6 %) Uncertain tax position 4.2 % 19.1 % 4.4 % 6.9 % Tax credits ( 8.5 %) ( 1.3 %) ( 8.5 %) ( 1.3 %) Effective tax rate 13.8 % 1.4 % 20.0 % 9.4 % The prior year tax adjustments, uncertain tax position and tax credits recognized during the three and nine months ended September 30, 2024 and 2023 are both primarily related to the Research & Experimentation (“R&E”) credits. The Company’s effective income tax rate was higher for the three months and nine months ended September 30, 2024 as compared to the three months and nine months ended September 30, 2023 primarily due to restructuring of the ownership of the Company’s Canadian entities and the deduction for worthless stock related to the wind-down of the Company’s commercial marketing business in the United Kingdom (the “U.K.”) during the second and the third quarters of 2023, respectively, which reduced the Company’s 2023 effective tax rate.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2024
Stockholders' Equity Note [Abstract]
Stockholders' Equity	NOTE 9 – STOCKHOLDERS’ EQUITY Accumulated Other Comprehensive Loss Accumulated other comprehensive loss as of September 30, 2024 and 2023 included the following: Three Months Ended September 30, 2024 Foreign Change in Total Accumulated other comprehensive (loss) income at June 30, 2024 $ ( 14,463 ) $ 2,919 $ ( 11,544 ) Current period other comprehensive (loss) income: Other comprehensive (loss) income before reclassifications 4,745 ( 5,099 ) ( 354 ) Amounts reclassified from accumulated other comprehensive (loss) income (1) — ( 1,670 ) ( 1,670 ) Effect of taxes ( 758 ) 1,831 1,073 Total current period other comprehensive (loss) income 3,987 ( 4,938 ) ( 951 ) Accumulated other comprehensive (loss) income at September 30, 2024 $ ( 10,476 ) $ ( 2,019 ) $ ( 12,495 ) Three Months Ended September 30, 2023 Foreign Change in Total Accumulated other comprehensive (loss) income at June 30, 2023 $ ( 10,833 ) $ 4,517 $ ( 6,316 ) Current period other comprehensive (loss) income: Other comprehensive (loss) income before reclassifications ( 3,487 ) 4,379 892 Amounts reclassified from accumulated other comprehensive (loss) income — ( 2,101 ) ( 2,101 ) Effect of taxes ( 2,227 ) ( 617 ) ( 2,844 ) Total current period other comprehensive (loss) income ( 5,714 ) 1,661 ( 4,053 ) Accumulated other comprehensive (loss) income at September 30, 2023 $ ( 16,547 ) $ 6,178 $ ( 10,369 ) Nine Months Ended September 30, 2024 Foreign Change in Total Accumulated other comprehensive (loss) income at December 31, 2023 $ ( 12,695 ) $ 810 $ ( 11,885 ) Current period other comprehensive (loss) income: Other comprehensive (loss) income before reclassifications 2,877 1,161 4,038 Amounts reclassified from accumulated other comprehensive (loss) income (1) — ( 5,002 ) ( 5,002 ) Effect of taxes ( 658 ) 1,012 354 Total current period other comprehensive (loss) income 2,219 ( 2,829 ) ( 610 ) Accumulated other comprehensive (loss) income at September 30, 2024 $ ( 10,476 ) $ ( 2,019 ) $ ( 12,495 ) Nine Months Ended September 30, 2023 Foreign Change in Total Accumulated other comprehensive (loss) income at December 31, 2022 $ ( 14,056 ) $ 5,923 $ ( 8,133 ) Current period other comprehensive (loss) income: Other comprehensive (loss) income before reclassifications ( 82 ) 5,658 5,576 Amounts reclassified from accumulated other comprehensive (loss) income — ( 5,299 ) ( 5,299 ) Effect of taxes ( 2,409 ) ( 104 ) ( 2,513 ) Total current period other comprehensive (loss) income ( 2,491 ) 255 ( 2,236 ) Accumulated other comprehensive (loss) income at September 30, 2023 $ ( 16,547 ) $ 6,178 $ ( 10,369 ) (1) The Company expects to reclassify $ 1.1 million of gains related to the Change in Fair Value of Interest Rate Hedge Agreements from accumulated other comprehensive (loss) income into earnings during the next 12 months. Share Repurchases The Company repurchased shares under the $ 200.0 million share repurchase program authorized by the Company’s board of directors. In addition, the Company repurchased shares in connection with the vesting of restricted stock units (“RSUs”) and performance share awards (“PSAs”) granted to employees. Repurchases for the three and nine months ended September 30, 2024 and 2023 are as follows: Three Months Ended September 30, 2024 2023 Shares Amount Paid Shares Amount Paid Share Repurchase Program — $ — — $ — Vesting of RSUs 2,383 377 91 12 Total 2,383 $ 377 91 $ 12 Nine Months Ended September 30, 2024 2023 Shares Amount Paid Shares Amount Paid Share Repurchase Program 191,000 $ 26,519 180,000 $ 18,126 Vesting of RSUs and PSAs 48,414 7,047 45,467 4,743 Total 239,414 $ 33,566 225,467 $ 22,869

Stock-based Compensation

Stock-based Compensation	9 Months Ended
	Sep. 30, 2024
Share-Based Payment Arrangement [Abstract]
Stock-based Compensation	NOTE 10 – STOCK-BASED COMPENSATION The Company’s 2018 Amended and Restated Omnibus Incentive Plan (the “2018 A&R Omnibus Plan”) allows the Company to grant up to 2,050,000 total shares of common stock to officers, key employees, and non-employee directors. As of September 30, 2024, the Company had approximately 1,018,803 shares available for grant under the 2018 A&R Omnibus Plan. The following awards were granted during the three and nine months ended September 30, 2024 and 2023: Awards Granted Average Grant Date Fair Value Awards Granted Average Grant Date Fair Value Three Months Ended Three Months Ended Nine Months Ended Nine Months Ended September 30, September 30, September 30, September 30, 2024 2023 2024 2023 2024 2023 2024 2023 Employee Stock Awards 672 — $ 153.50 $ — 83,467 113,569 $ 152.59 $ 107.29 Cash-Settled RSUs 3,012 2,281 $ 153.50 $ 130.47 37,570 68,745 $ 152.64 $ 110.04 Non-Employee Director Stock Awards 6,618 8,211 $ 135.91 $ 127.81 6,618 8,211 $ 135.91 $ 127.81 Total 10,302 10,492 127,655 190,525 The total stock-based compensation expense was $ 6.6 million and $ 19.3 million for the three and nine months ended September 30, 2024, respectively, and $ 5.2 million and $ 15.9 million for the three and nine months ended September 30, 2023, respectively. The unrecognized compensation expense at September 30, 2024 was $ 34.0 million , which is expected to vest over the next 1.5 years.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2024
Earnings Per Share [Abstract]
Earnings Per Share	NOTE 11 – EARNINGS PER SHARE The Company’s earnings per share (“EPS”) is computed by dividing reported net income by the weighted-average number of shares outstanding. Diluted EPS (“U.S. GAAP Diluted EPS”) considers the potential dilution that could occur if the Company’s common stock options, RSUs, and PSAs were exercised or converted into the Company’s common stock. PSAs are included in the computation of diluted shares only to the extent that the underlying performance conditions: (i) are satisfied as of the end of the reporting period or (ii) would be considered satisfied if the end of the reporting period were the end of the related performance period and the result would be dilutive under the treasury stock method. As of September 30, 2024, the PSAs granted during the year ended December 31, 2022 met the related performance conditions for the initial performance period and were included in the calculation of U.S. GAAP Diluted EPS. However, the PSAs granted during the year ended December 31, 2023 and during the nine months ended September 30, 2024 have not yet completed their initial two-year performance period and therefore were excluded from the calculation of U.S. GAAP Diluted EPS. EPS, including the dilutive effect of stock awards for each period reported is summarized below: Three Months Ended Nine Months Ended September 30, September 30, (in thousands, except per share data) 2024 2023 2024 2023 Net Income $ 32,679 $ 23,740 $ 85,607 $ 60,450 Weighted-average number of basic shares outstanding during the period 18,760 18,815 18,752 18,795 Dilutive effect of stock awards 150 159 163 163 Weighted-average number of diluted shares outstanding during the period 18,910 18,974 18,915 18,958 Basic EPS $ 1.74 $ 1.26 $ 4.57 $ 3.22 Diluted EPS $ 1.73 $ 1.25 $ 4.53 $ 3.19 A total of 324 and 190 shares of restricted stock awards were excluded from the calculation of EPS for the three and nine months ended September 30, 2024 because they were anti-dilutive. There were no shares excluded for the three and nine months ended September 30, 2023 .

Fair Value

Fair Value	9 Months Ended
	Sep. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value	NOTE 12 – FAIR VALUE Financial instruments measured at fair value on a recurring basis and their location within the accompanying consolidated balance sheets are as follows: September 30, 2024 (in thousands) Level 1 Level 2 Level 3 Total Location on Balance Sheet Assets: Interest rate swaps - current portion $ — $ 1,674 $ — $ 1,674 Prepaid expenses and other assets Company-owned life insurance policies — 23,160 — 23,160 Other assets Liabilities: Interest rate swaps - current portion $ — $ 564 $ — $ 564 Accrued expenses and other current liabilities Interest rate swaps - long-term portion — 3,917 — 3,917 Other long-term liabilities December 31, 2023 (in thousands) Level 1 Level 2 Level 3 Total Location on Balance Sheet Assets: Interest rate swaps - current portion $ — $ 4,820 $ — $ 4,820 Prepaid expenses and other assets Interest rate swaps - long-term portion — 398 — 398 Other assets Company-owned life insurance policies — 20,438 — 20,438 Other assets Liabilities: Interest rate swaps - long-term portion $ — $ 4,184 $ — $ 4,184 Other long-term liabilities

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	NOTE 13 – COMMITMENTS AND CONTINGENCIES Letters of Credit The Company had open standby letters of credit totaling $ 1.8 million at both September 30, 2024 and December 31, 2023, respectively. Open standby letters of credit reduce the Company’s borrowing capacity under the Credit Facility. Guarantees At September 30, 2024 and December 31, 2023 , the Company had $ 6.5 million and $ 7.9 million, respectively, of bank guarantees for facility leases and contract performance obligations. Litigation and Claims The Company is involved in various legal matters and proceedings arising in the ordinary course of business. While these matters and proceedings cause it to incur costs, including, but not limited to, attorneys’ fees, the Company currently believes that any ultimate liability arising out of these matters and proceedings will not have a material adverse effect on its financial position, results of operations, or cash flows.

Basis of Presentation (Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying consolidated financial statements are of ICF International, Inc. (“ICFI”) and its principal subsidiary, ICF Consulting Group, Inc. (“Consulting,” and together with ICFI, the “Company”), and have been prepared in accordance with United States (“U.S.”) generally accepted accounting principles (“U.S. GAAP”). Consulting is a wholly owned subsidiary of ICFI. ICFI is a holding company with no operations or assets other than its investment in the common stock of Consulting. All other subsidiaries of the Company are wholly owned by Consulting. Intercompany transactions and balances have been eliminated. The terms “federal” or “federal government” refer to the U.S. federal government, and “state and local” or “state and local government” refer to U.S. state (including territories) and local governments, unless otherwise indicated.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities, and the reported amounts of revenue and expenses. Key estimates include estimates related to variable consideration on contracts with customers, costs to complete fixed-price contracts, bonus and other incentive compensation, reserves for tax benefits and valuation allowances on deferred tax assets, collectability of receivables, valuation and useful lives of acquired tangible and intangible assets, impairment of goodwill and long-lived assets, and contingencies. Actual results experienced by the Company may differ from management’s estimates.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Recent Accounting Pronouncements Not Yet Adopted Segment Reporting In November 2023, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) 2023-07: Improvements to Reportable Segment Disclosures to update reportable segment disclosure requirements for public entities under the Accounting Standards Codification (“ASC”). ASU 2023-07 enhances the current segment reporting disclosures of Topic 280 by requiring disclosure of significant segment expenses that are regularly reviewed by the Chief Operating Decision Maker (the “CODM”), the amount and description of other segment items, and interim disclosures of each reportable segment’s profit or loss and assets. ASU 2023-07 also requires public entities that have a single reportable segment to provide all of the disclosures required in Topic 280, as amended. ASU 2023-07 is effective for the Company for the fiscal year ending December 31, 2024 and interim periods within the 2025 fiscal year on a retrospective basis, with early adoption permitted. The Company expects to adopt the amendments of ASU 2023-07 for the fiscal year ending December 31, 2024, but does not expect the adoption to have a material impact, if any, on the consolidated financial statements. Income Taxes In December 2023, the FASB issued ASU 2023-09, Income Taxes: Improvements to Income Tax Disclosures, which requires greater disaggregation of income tax rates and amounts paid by entities. ASU 2023-09 specifically requires all entities to disclose, on an annual basis, disaggregated domestic and foreign pre-tax income or loss from continuing operations and the disaggregated income tax expense or benefit by federal, state, and foreign components, and a tabular rate reconciliation, using both percentages and reporting currency amounts, of eight specific categories as well as any individual reconciling items that are equal to or greater than 5% of a threshold computed by multiplying pretax income or loss from continuing operations by the applicable federal rate. Additionally, the amendments also require disclosure of income taxes paid disaggregated by federal, state, and foreign jurisdictions as well as any individual jurisdictions over 5% of the total income taxes paid. ASU 2023-09 is effective for the Company for the fiscal year ending December 31, 2025, with early adoption permitted. The amendments may be adopted on a prospective or retrospective basis. The Company is currently evaluating the impact of the adoption of ASU 2023-09 but does not expect the adoption to have a material impact, if any, on the consolidated financial statements.

Restricted Cash (Tables)

Restricted Cash (Tables)	9 Months Ended
	Sep. 30, 2024
Restricted Cash and Cash Equivalents, Current [Abstract]
Reconciliation of Cash and Cash Equivalents, and Restricted Cash	The following table provides a reconciliation of cash and cash equivalents and restricted cash reported within the consolidated balance sheets for the periods presented to the total of cash, cash equivalents, and restricted cash shown in the consolidated statements of cash flows for the nine months ended September 30, 2024 and 2023: September 30, 2024 September 30, 2023 Beginning Ending Beginning Ending Cash and cash equivalents $ 6,361 $ 6,911 $ 11,257 $ 5,084 Restricted cash 3,088 724 1,711 2,770 Total of cash, cash equivalents, and restricted cash shown in the consolidated statements of cash flows $ 9,449 $ 7,635 $ 12,968 $ 7,854

Contract Receivables, Net (Tabl

Contract Receivables, Net (Tables)	9 Months Ended
	Sep. 30, 2024
Receivables [Abstract]
Summary of Contract Receivables, Net	Contract receivables, net consisted of the following: September 30, 2024 December 31, 2023 Billed and billable $ 220,690 $ 210,919 Allowance for expected credit losses ( 8,278 ) ( 5,435 ) Contract receivables, net $ 212,412 $ 205,484
Summary of Reconciliation of Billed Contract Receivables Sold to MUF Including Receivables Sold to MUFC And Collected from Customers on Behalf of MUFG And Receivables Not Yet Collected from Customers	The following is a reconciliation of billed contract receivables sold to MUFG that were eligible and accounted for as sales under ASC 860, including billed contract receivables sold to MUFG and collected from customers on behalf of MUFG during the nine months ended September 30, 2024 and 2023, and the balance of billed contract receivables not yet collected from customers as of September 30, 2024 and 2023, respectively: As of and for the Nine Months Ended September 30, 2024 September 30, 2023 Beginning balance, billed contract receivables sold and not yet collected (1) $ 21,302 $ 3,819 Billed contract receivables sold during the period (2) 482,469 159,480 Collections from customers during the period (2) ( 473,037 ) ( 131,580 ) Ending balance, billed contract receivables sold and not yet collected (3) $ 30,735 $ 31,719 (1) The beginning balances represent billed contract receivables that were previously sold and derecognized by the Company but have not yet been collected from customers as of January 1, 2024 and 2023 , respectively. (2) For the nine months ended September 30, 2024 and 2023, the Company recorded net inflows of $ 9.4 million and $ 27.9 million , respectively, in its cash flows from operating activities from the sale of billed contract receivables. (3) The ending balances represent billed contract receivables that were sold and derecognized by the Company but have not yet been collected from customers as of September 30, 2024 and 2023 , respectively.
Summary of Reconciliation of Cash Collections from Customers of Billed Contract Receivables Previously Sold to MUFG Including Previous Sold Receivables And Remittance of Cash Collections to MUFG And Cash Collected But Not Yet Remitted to MUFG	The following is a reconciliation of cash collections from customers of billed contract receivables previously sold to MUFG that were eligible and accounted for as sales under ASC 860, including collections from customers on behalf of MUFG of previously sold billed contract receivables and remittances of cash collections to MUFG during the nine months ended September 30, 2024 and 2023, and the balance of cash collected but not yet remitted to MUFG as of September 30, 2024 and 2023, respectively: As of and for the Nine Months Ended September 30, 2024 September 30, 2023 Beginning balance, cash collected but not yet remitted to MUFG (1) $ 21,796 $ 6,164 Collections from customers during the period (2) 473,037 131,580 Remittances to MUFG during the period (2) ( 463,558 ) ( 127,303 ) Ending balance, cash collected but not yet remitted to MUFG (3) $ 31,275 $ 10,441 (1) The beginning balances represent cash collected from customers on behalf of MUFG for billed contract receivables that were previously sold and derecognized by the Company but have not yet been remitted to MUFG as of January 1, 2024 and 2023 , respectively. (2) For the nine months ended September 30, 2024 and 2023, the Company recorded net inflows of $ 9.5 million and $ 4.3 million , respectively, in its cash flows from operating activities from the collection of billed contract receivables that were sold but not yet remitted to MUFG. (3) The ending balances are included as part of “Accrued expenses and other current liabilities” on the Company’s consolidated balance sheets.

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2024
Leases [Abstract]
Summary of Future Minimum Lease Payments Under Non-Cancellable Operating and Finance Leases	Future minimum lease payments under non-cancellable operating and finance leases as of September 30, 2024 were as follows: Operating Finance September 30, 2025 $ 27,037 $ 3,041 September 30, 2026 23,268 3,041 September 30, 2027 20,171 3,041 September 29, 2028 16,515 3,004 September 30, 2029 14,065 2,967 Thereafter 121,325 741 Total future minimum lease payments 222,381 15,835 Less: Interest ( 40,251 ) ( 1,323 ) Total lease liabilities $ 182,130 $ 14,512 Lease liabilities - current $ 21,204 $ 2,590 Lease liabilities - non-current 160,926 11,922 Total lease liabilities $ 182,130 $ 14,512

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2024
Debt Disclosure [Abstract]
Schedule of Debt	At September 30, 2024 and December 31, 2023, debt consisted of: September 30, 2024 December 31, 2023 Average Outstanding Average Outstanding Term Loan $ 200,250 $ 207,750 Delayed-Draw Term Loan 211,750 220,000 Revolving Credit 10,000 6,340 Total before debt issuance costs 6.8 % 422,000 6.7 % 434,090 Unamortized debt issuance costs ( 2,854 ) ( 3,683 ) Total $ 419,146 $ 430,407 September 30, 2024 December 31, 2023 Current portion of long-term debt $ 13,750 $ 26,000 Long-term debt - non-current 405,396 404,407 Total $ 419,146 $ 430,407
Schedule of Future Contractual Repayments of Debt Principal	Future contractual repayments of debt principal are as follows: Payments due by Term Loan Delayed-Draw Term Loan Revolving Credit Total September 30, 2025 $ — $ 13,750 $ — $ 13,750 September 30, 2026 — 16,500 — 16,500 May 6, 2027 (Maturity) 200,250 181,500 10,000 391,750 Total $ 200,250 $ 211,750 $ 10,000 $ 422,000

Revenue Recognition (Tables)

Revenue Recognition (Tables)	9 Months Ended
	Sep. 30, 2024
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The Company disaggregates revenue from clients into categories that depict how the nature, amount, and uncertainty of revenue and cash flows are affected by economic and business factors. Those categories are client market, client type, and contract mix. Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Dollars Percent Dollars Percent Dollars Percent Dollars Percent Client Markets: Energy, environment, infrastructure, and disaster recovery $ 236,039 46 % $ 204,740 41 % $ 693,229 46 % $ 595,769 40 % Health and social programs 196,586 38 % 209,760 42 % 582,191 38 % 617,997 42 % Security and other civilian & commercial 84,373 16 % 87,019 17 % 248,043 16 % 271,120 18 % Total $ 516,998 100 % $ 501,519 100 % $ 1,523,463 100 % $ 1,484,886 100 % Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Dollars Percent Dollars Percent Dollars Percent Dollars Percent Client Type: U.S. federal government $ 282,022 55 % $ 279,314 56 % $ 829,688 55 % $ 820,116 55 % U.S. state and local government 78,883 15 % 76,594 15 % 240,685 16 % 233,264 16 % International government 26,871 5 % 27,547 5 % 80,831 5 % 74,378 5 % Total Government 387,776 75 % 383,455 76 % 1,151,204 76 % 1,127,758 76 % Commercial 129,222 25 % 118,064 24 % 372,259 24 % 357,128 24 % Total $ 516,998 100 % $ 501,519 100 % $ 1,523,463 100 % $ 1,484,886 100 % Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Dollars Percent Dollars Percent Dollars Percent Dollars Percent Contract Mix: Time-and-materials $ 220,564 43 % $ 206,622 41 % $ 644,822 42 % $ 615,902 41 % Fixed-price 236,538 46 % 223,338 45 % 696,211 46 % 667,982 45 % Cost-based 59,896 11 % 71,559 14 % 182,430 12 % 201,002 14 % Total $ 516,998 100 % $ 501,519 100 % $ 1,523,463 100 % $ 1,484,886 100 %
Schedule of Contract Assets and Liabilities	The following table summarizes the contract assets and liabilities as of September 30, 2024 and December 31, 2023: September 30, 2024 December 31, 2023 Contract assets $ 237,742 $ 201,832 Contract liabilities ( 17,176 ) ( 21,997 ) Net contract assets (liabilities) $ 220,566 $ 179,835

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2024
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation	A r econciliation of the Company’s statutory rate to the effective tax rate for the three and nine months ended September 30, 2024 and 2023 is as follows: Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Statutory tax rate 21.0 % 21.0 % 21.0 % 21.0 % State taxes, net of federal benefit 6.0 % 5.8 % 6.0 % 5.8 % Executive compensation 1.6 % 1.4 % 1.6 % 1.4 % Corporate-owned life insurance ( 0.5 %) ( 0.2 %) ( 0.5 %) ( 0.2 %) Other permanent differences 0.4 % 0.4 % 0.4 % 0.3 % Prior year tax adjustments ( 11.0 %) ( 27.1 %) ( 3.7 %) ( 10.8 %) Worthless stock — ( 20.2 %) — ( 7.3 %) Capital loss — — — ( 6.7 %) Valuation allowance 0.9 % 3.1 % 1.0 % 1.9 % Equity-based compensation ( 0.3 %) ( 0.6 %) ( 1.7 %) ( 1.6 %) Uncertain tax position 4.2 % 19.1 % 4.4 % 6.9 % Tax credits ( 8.5 %) ( 1.3 %) ( 8.5 %) ( 1.3 %) Effective tax rate 13.8 % 1.4 % 20.0 % 9.4 % The prior year tax adjustments, uncertain tax position and tax credits recognized during the three and nine months ended September 30, 2024 and 2023 are both primarily related to the Research & Experimentation (“R&E”) credits.

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2024
Stockholders' Equity Note [Abstract]
Components of Accumulated Other Comprehensive Loss	Accumulated other comprehensive loss as of September 30, 2024 and 2023 included the following: Three Months Ended September 30, 2024 Foreign Change in Total Accumulated other comprehensive (loss) income at June 30, 2024 $ ( 14,463 ) $ 2,919 $ ( 11,544 ) Current period other comprehensive (loss) income: Other comprehensive (loss) income before reclassifications 4,745 ( 5,099 ) ( 354 ) Amounts reclassified from accumulated other comprehensive (loss) income (1) — ( 1,670 ) ( 1,670 ) Effect of taxes ( 758 ) 1,831 1,073 Total current period other comprehensive (loss) income 3,987 ( 4,938 ) ( 951 ) Accumulated other comprehensive (loss) income at September 30, 2024 $ ( 10,476 ) $ ( 2,019 ) $ ( 12,495 ) Three Months Ended September 30, 2023 Foreign Change in Total Accumulated other comprehensive (loss) income at June 30, 2023 $ ( 10,833 ) $ 4,517 $ ( 6,316 ) Current period other comprehensive (loss) income: Other comprehensive (loss) income before reclassifications ( 3,487 ) 4,379 892 Amounts reclassified from accumulated other comprehensive (loss) income — ( 2,101 ) ( 2,101 ) Effect of taxes ( 2,227 ) ( 617 ) ( 2,844 ) Total current period other comprehensive (loss) income ( 5,714 ) 1,661 ( 4,053 ) Accumulated other comprehensive (loss) income at September 30, 2023 $ ( 16,547 ) $ 6,178 $ ( 10,369 ) Nine Months Ended September 30, 2024 Foreign Change in Total Accumulated other comprehensive (loss) income at December 31, 2023 $ ( 12,695 ) $ 810 $ ( 11,885 ) Current period other comprehensive (loss) income: Other comprehensive (loss) income before reclassifications 2,877 1,161 4,038 Amounts reclassified from accumulated other comprehensive (loss) income (1) — ( 5,002 ) ( 5,002 ) Effect of taxes ( 658 ) 1,012 354 Total current period other comprehensive (loss) income 2,219 ( 2,829 ) ( 610 ) Accumulated other comprehensive (loss) income at September 30, 2024 $ ( 10,476 ) $ ( 2,019 ) $ ( 12,495 ) Nine Months Ended September 30, 2023 Foreign Change in Total Accumulated other comprehensive (loss) income at December 31, 2022 $ ( 14,056 ) $ 5,923 $ ( 8,133 ) Current period other comprehensive (loss) income: Other comprehensive (loss) income before reclassifications ( 82 ) 5,658 5,576 Amounts reclassified from accumulated other comprehensive (loss) income — ( 5,299 ) ( 5,299 ) Effect of taxes ( 2,409 ) ( 104 ) ( 2,513 ) Total current period other comprehensive (loss) income ( 2,491 ) 255 ( 2,236 ) Accumulated other comprehensive (loss) income at September 30, 2023 $ ( 16,547 ) $ 6,178 $ ( 10,369 ) (1) The Company expects to reclassify $ 1.1 million of gains related to the Change in Fair Value of Interest Rate Hedge Agreements from accumulated other comprehensive (loss) income into earnings during the next 12 months.
Summary of Repurchases of Shares	Repurchases for the three and nine months ended September 30, 2024 and 2023 are as follows: Three Months Ended September 30, 2024 2023 Shares Amount Paid Shares Amount Paid Share Repurchase Program — $ — — $ — Vesting of RSUs 2,383 377 91 12 Total 2,383 $ 377 91 $ 12 Nine Months Ended September 30, 2024 2023 Shares Amount Paid Shares Amount Paid Share Repurchase Program 191,000 $ 26,519 180,000 $ 18,126 Vesting of RSUs and PSAs 48,414 7,047 45,467 4,743 Total 239,414 $ 33,566 225,467 $ 22,869

Stock-based Compensation (Table

Stock-based Compensation (Tables)	9 Months Ended
	Sep. 30, 2024
Share-Based Payment Arrangement, Recognized Amount [Abstract]
Schedule of Awards Granted	The following awards were granted during the three and nine months ended September 30, 2024 and 2023: Awards Granted Average Grant Date Fair Value Awards Granted Average Grant Date Fair Value Three Months Ended Three Months Ended Nine Months Ended Nine Months Ended September 30, September 30, September 30, September 30, 2024 2023 2024 2023 2024 2023 2024 2023 Employee Stock Awards 672 — $ 153.50 $ — 83,467 113,569 $ 152.59 $ 107.29 Cash-Settled RSUs 3,012 2,281 $ 153.50 $ 130.47 37,570 68,745 $ 152.64 $ 110.04 Non-Employee Director Stock Awards 6,618 8,211 $ 135.91 $ 127.81 6,618 8,211 $ 135.91 $ 127.81 Total 10,302 10,492 127,655 190,525

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2024
Earnings Per Share [Abstract]
Schedule of EPS Including Dilutive Effect of Stock Awards	EPS, including the dilutive effect of stock awards for each period reported is summarized below: Three Months Ended Nine Months Ended September 30, September 30, (in thousands, except per share data) 2024 2023 2024 2023 Net Income $ 32,679 $ 23,740 $ 85,607 $ 60,450 Weighted-average number of basic shares outstanding during the period 18,760 18,815 18,752 18,795 Dilutive effect of stock awards 150 159 163 163 Weighted-average number of diluted shares outstanding during the period 18,910 18,974 18,915 18,958 Basic EPS $ 1.74 $ 1.26 $ 4.57 $ 3.22 Diluted EPS $ 1.73 $ 1.25 $ 4.53 $ 3.19

Fair Value (Tables)

Fair Value (Tables)	9 Months Ended
	Sep. 30, 2024
Fair Value Disclosures [Abstract]
Schedule of Financial Instruments Measured at Fair Value on Recurring Basis	Financial instruments measured at fair value on a recurring basis and their location within the accompanying consolidated balance sheets are as follows: September 30, 2024 (in thousands) Level 1 Level 2 Level 3 Total Location on Balance Sheet Assets: Interest rate swaps - current portion $ — $ 1,674 $ — $ 1,674 Prepaid expenses and other assets Company-owned life insurance policies — 23,160 — 23,160 Other assets Liabilities: Interest rate swaps - current portion $ — $ 564 $ — $ 564 Accrued expenses and other current liabilities Interest rate swaps - long-term portion — 3,917 — 3,917 Other long-term liabilities December 31, 2023 (in thousands) Level 1 Level 2 Level 3 Total Location on Balance Sheet Assets: Interest rate swaps - current portion $ — $ 4,820 $ — $ 4,820 Prepaid expenses and other assets Interest rate swaps - long-term portion — 398 — 398 Other assets Company-owned life insurance policies — 20,438 — 20,438 Other assets Liabilities: Interest rate swaps - long-term portion $ — $ 4,184 $ — $ 4,184 Other long-term liabilities

Basis of Presentation - Additio

Basis of Presentation - Additional Information (Details) - Segment	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating segments	1	1	1	1
Number of reporting segments	1	1	1	1

Restricted Cash - Reconciliatio

Restricted Cash - Reconciliation of Cash and Cash Equivalents, and Restricted Cash to the Total of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 6,911	$ 6,361	$ 5,084	$ 11,257
Restricted cash	724	3,088	2,770	1,711
Total of cash, cash equivalents, and restricted cash shown in the consolidated statements of cash flows	$ 7,635	$ 9,449	$ 7,854	$ 12,968

Contract Receivables, Net - Sum

Contract Receivables, Net - Summary of Contract Receivables, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Receivables [Abstract]
Billed and billable	$ 220,690	$ 210,919
Allowance for expected credit losses	(8,278)	(5,435)
Contract receivables, net	$ 212,412	$ 205,484

Contract Receivables, Net -Summ

Contract Receivables, Net -Summary of Reconciliation of Billed Contract Receivables Sold to MUF Including Receivables Sold to MUFC And Collected from Customers on Behalf of MUFG And Receivables Not Yet Collected from Customers (Details) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2024	Sep. 30, 2023
Receivables [Abstract]
Beginning balance	[1]	$ 21,302	$ 3,819
Billed receivables sold during the period	[2]	482,469	159,480
Collections from customers during the period	[2],[3]	(473,037)	(131,580)
Ending balance	[4]	$ 30,735	$ 31,719
[1] The beginning balances represent billed contract receivables that were previously sold and derecognized by the Company but have not yet been collected from customers as of January 1, 2024 and 2023 , respectively. For the nine months ended September 30, 2024 and 2023, the Company recorded net inflows of $ 9.4 million and $ 27.9 million , respectively, in its cash flows from operating activities from the sale of billed contract receivables. For the nine months ended September 30, 2024 and 2023, the Company recorded net inflows of $ 9.5 million and $ 4.3 million , respectively, in its cash flows from operating activities from the collection of billed contract receivables that were sold but not yet remitted to MUFG. The ending balances represent billed contract receivables that were sold and derecognized by the Company but have not yet been collected from customers as of September 30, 2024 and 2023 , respectively.

Contract Receivables, Net - S_2

Contract Receivables, Net - Summary of Reconciliation of Billed Contract Receivables Sold to MUF Including Receivables Sold to MUFC And Collected from Customers on Behalf of MUFG And Receivables Not Yet Collected from Customers (Parenthetical) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Receivables [Abstract]
Proceeds from sale of billed contract receivables	$ 9.4	$ 27.9

Contract Receivables, Net - S_3

Contract Receivables, Net - Summary of Reconciliation of Cash Collections from Customers of Billed Contract Receivables Previously Sold to MUFG Including Previous Sold Receivables And Remittance of Cash Collections to MUFG And Cash Collected But Not Yet Remitted to MUFG (Details) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2024	Sep. 30, 2023
Receivables [Abstract]
Beginning balance	[1]	$ 21,796	$ 6,164
Collections from customers during the period	[2],[3]	473,037	131,580
Remittances to MUFG during the period	[3]	(463,558)	(127,303)
Ending balance	[4]	$ 31,275	$ 10,441
[1] The beginning balances represent cash collected from customers on behalf of MUFG for billed contract receivables that were previously sold and derecognized by the Company but have not yet been remitted to MUFG as of January 1, 2024 and 2023 , respectively. For the nine months ended September 30, 2024 and 2023, the Company recorded net inflows of $ 9.4 million and $ 27.9 million , respectively, in its cash flows from operating activities from the sale of billed contract receivables. For the nine months ended September 30, 2024 and 2023, the Company recorded net inflows of $ 9.5 million and $ 4.3 million , respectively, in its cash flows from operating activities from the collection of billed contract receivables that were sold but not yet remitted to MUFG. The ending balances are included as part of “Accrued expenses and other current liabilities” on the Company’s consolidated balance sheets.

Contract Receivables, Net - S_4

Contract Receivables, Net - Summary of Reconciliation of Cash Collections from Customers of Billed Contract Receivables Previously Sold to MUFG Including Previous Sold Receivables And Remittance of Cash Collections to MUFG And Cash Collected But Not Yet Remitted to MUFG (Parenthetical) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024		Sep. 30, 2023		Dec. 31, 2023	[2]	Dec. 31, 2022	[2]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Procceds from sale of billed receivables but not yet remitted to MUFG	$ 9,500		$ 4,300
Sale of billed receivables	$ 31,275	[1]	$ 10,441	[1]	$ 21,796		$ 6,164
[1] The ending balances are included as part of “Accrued expenses and other current liabilities” on the Company’s consolidated balance sheets. The beginning balances represent cash collected from customers on behalf of MUFG for billed contract receivables that were previously sold and derecognized by the Company but have not yet been remitted to MUFG as of January 1, 2024 and 2023 , respectively.

Contract Receivables, Net - Add

Contract Receivables, Net - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Financing Receivable, Past Due [Line Items]
Sale of billed contract receivables amount	$ 18.9	$ 32.2
Master Receivables Purchase Agreement with MUFG Bank
Financing Receivable, Past Due [Line Items]
Cash collected not yet remitted for receivables sold	$ 2.7		$ 6.9

Leases - Additional Information

Leases - Additional Information (Details)	Sep. 30, 2024
Minimum
Lessee Lease Description [Line Items]
Operating leases, remaining lease term	1 year
Finance leases, remaining lease term	1 year
Maximum
Lessee Lease Description [Line Items]
Operating leases, remaining lease term	14 years
Finance leases, remaining lease term	14 years

Leases - Summary of Future Mini

Leases - Summary of Future Minimum Lease Payments Under Non-Cancellable Operating and Finance Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Leases [Abstract]
September 30, 2025	$ 27,037
September 30, 2026	23,268
September 30, 2027	20,171
September 30, 2028	16,515
September 30, 2029	14,065
Thereafter	121,325
Total future minimum lease payments	222,381
Less: Interest	(40,251)
Total lease liabilities	182,130
Lease liabilities - current	21,204	$ 20,409
Lease liabilities - non-current	160,926	175,460
September 30, 2025	3,041
September 30, 2026	3,041
September 30, 2027	3,041
September 30, 2028	3,004
September 30, 2029	2,967
Thereafter	741
Total future minimum lease payments	15,835
Less: Interest	(1,323)
Total lease liabilities	14,512
Lease liabilities - current	2,590	2,522
Lease liabilities - non-current	$ 11,922	$ 13,874

Debt - Schedule of Debt (Detail

Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Average Interest Rate	6.80%	6.70%
Outstanding Balance before debt issuance costs	$ 422,000	$ 434,090
Unamortized debt issuance costs	(2,854)	(3,683)
Current portion of long-term debt	13,750	26,000
Long-term debt - non-current	405,396	404,407
Total	419,146	430,407
Term Loan
Debt Instrument [Line Items]
Outstanding Balance before debt issuance costs	200,250	207,750
Delayed-Draw Term Loan
Debt Instrument [Line Items]
Outstanding Balance before debt issuance costs	211,750	220,000
Revolving Credit
Debt Instrument [Line Items]
Outstanding Balance before debt issuance costs	$ 10,000	$ 6,340

Debt - Additional Information (

Debt - Additional Information (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Letters of credit outstanding, amount	$ 1,800,000
Interest Rate Swap | Cash Flow Hedging | Designated as Hedging Instrument
Debt Instrument [Line Items]
Derivative fixed interest rate	5.40%	5.60%
Revolving Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 600,000,000
Unused borrowing capacity amount	$ 588,200,000
Interest rate on credit facility	6.80%	6.70%

Debt - Schedule of Future Contr

Debt - Schedule of Future Contractual Repayments of Debt Principal (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
September 30, 2025	$ 13,750
September 30, 2026	16,500
May 6, 2027 (Maturity)	391,750
Total	422,000	$ 434,090
Term Loan
Debt Instrument [Line Items]
May 6, 2027 (Maturity)	200,250
Total	200,250	207,750
Delayed-Draw Term Loan
Debt Instrument [Line Items]
September 30, 2025	13,750
September 30, 2026	16,500
May 6, 2027 (Maturity)	181,500
Total	211,750	220,000
Revolving Credit
Debt Instrument [Line Items]
May 6, 2027 (Maturity)	10,000
Total	$ 10,000	$ 6,340

Revenue Recognition - Disaggreg

Revenue Recognition - Disaggregation of Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Disaggregation Of Revenue [Line Items]
Revenue from clients	$ 516,998	$ 501,519	$ 1,523,463	$ 1,484,886
Time-and-Materials
Disaggregation Of Revenue [Line Items]
Revenue from clients	220,564	206,622	644,822	615,902
Fixed-Price
Disaggregation Of Revenue [Line Items]
Revenue from clients	236,538	223,338	696,211	667,982
Cost-Based
Disaggregation Of Revenue [Line Items]
Revenue from clients	59,896	71,559	182,430	201,002
U.S. Federal Government
Disaggregation Of Revenue [Line Items]
Revenue from clients	282,022	279,314	829,688	820,116
U.S. State and Local Government
Disaggregation Of Revenue [Line Items]
Revenue from clients	78,883	76,594	240,685	233,264
International Government
Disaggregation Of Revenue [Line Items]
Revenue from clients	26,871	27,547	80,831	74,378
Total Government
Disaggregation Of Revenue [Line Items]
Revenue from clients	387,776	383,455	1,151,204	1,127,758
Commercial
Disaggregation Of Revenue [Line Items]
Revenue from clients	$ 129,222	$ 118,064	$ 372,259	$ 357,128
Customer Concentration Risk | Revenue from Contract with Customer
Disaggregation Of Revenue [Line Items]
Revenue from clients, Percent	100%	100%	100%	100%
Customer Concentration Risk | Revenue from Contract with Customer | Time-and-Materials
Disaggregation Of Revenue [Line Items]
Revenue from clients, Percent	43%	41%	42%	41%
Customer Concentration Risk | Revenue from Contract with Customer | Fixed-Price
Disaggregation Of Revenue [Line Items]
Revenue from clients, Percent	46%	45%	46%	45%
Customer Concentration Risk | Revenue from Contract with Customer | Cost-Based
Disaggregation Of Revenue [Line Items]
Revenue from clients, Percent	11%	14%	12%	14%
Customer Concentration Risk | Revenue from Contract with Customer | U.S. Federal Government
Disaggregation Of Revenue [Line Items]
Revenue from clients, Percent	55%	56%	55%	55%
Customer Concentration Risk | Revenue from Contract with Customer | U.S. State and Local Government
Disaggregation Of Revenue [Line Items]
Revenue from clients, Percent	15%	15%	16%	16%
Customer Concentration Risk | Revenue from Contract with Customer | International Government
Disaggregation Of Revenue [Line Items]
Revenue from clients, Percent	5%	5%	5%	5%
Customer Concentration Risk | Revenue from Contract with Customer | Total Government
Disaggregation Of Revenue [Line Items]
Revenue from clients, Percent	75%	76%	76%	76%
Customer Concentration Risk | Revenue from Contract with Customer | Commercial
Disaggregation Of Revenue [Line Items]
Revenue from clients, Percent	25%	24%	24%	24%
Energy, Environment, Infrastructure, and Disaster Recovery
Disaggregation Of Revenue [Line Items]
Revenue from clients	$ 236,039	$ 204,740	$ 693,229	$ 595,769
Energy, Environment, Infrastructure, and Disaster Recovery | Customer Concentration Risk | Revenue from Contract with Customer
Disaggregation Of Revenue [Line Items]
Revenue from clients, Percent	46%	41%	46%	40%
Health and Social Programs
Disaggregation Of Revenue [Line Items]
Revenue from clients	$ 196,586	$ 209,760	$ 582,191	$ 617,997
Health and Social Programs | Customer Concentration Risk | Revenue from Contract with Customer
Disaggregation Of Revenue [Line Items]
Revenue from clients, Percent	38%	42%	38%	42%
Security and Other Civilian & Commercial
Disaggregation Of Revenue [Line Items]
Revenue from clients	$ 84,373	$ 87,019	$ 248,043	$ 271,120
Security and Other Civilian & Commercial | Customer Concentration Risk | Revenue from Contract with Customer
Disaggregation Of Revenue [Line Items]
Revenue from clients, Percent	16%	17%	16%	18%

Revenue Recognition - Schedule

Revenue Recognition - Schedule of Contract Assets and Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Contract assets	$ 237,742	$ 201,832
Contract liabilities	(17,176)	(21,997)
Net contract assets (liabilities)	$ 220,566	$ 179,835

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Revenue from Contract with Customer [Abstract]
Revenue related to contract liabilities	$ 17.1	$ 17.3

Revenue Recognition - Additio_2

Revenue Recognition - Additional Information (Detail 1) $ in Billions	Sep. 30, 2024 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2024-10-01
Revenue From Contract With Customer [Line Items]
Unfulfilled performance obligation	$ 1.4
Expected period to satisfy performance obligations	1 year
Revenue, remaining performance obligation, percentage	8%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2025-01-01
Revenue From Contract With Customer [Line Items]
Expected period to satisfy performance obligations	1 year
Revenue, remaining performance obligation, percentage	65%

Derivative Instruments and He_2

Derivative Instruments and Hedging Activities - Additional Information (Details) - Interest Rate Swap - Cash Flow Hedging - Designated as Hedging Instrument $ in Millions	9 Months Ended
	Sep. 30, 2024 USD ($)
Derivative [Line Items]
Notional amount	$ 275
June 27, 2028
Derivative [Line Items]
Notional amount	$ 100
Maturity date	Jun. 27, 2028
February 28, 2025
Derivative [Line Items]
Notional amount	$ 100
Maturity date	Feb. 28, 2025
February 28, 2028
Derivative [Line Items]
Notional amount	$ 75
Maturity date	Feb. 28, 2028

Income Taxes - Effective Income

Income Taxes - Effective Income Tax Rate Reconciliation (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Statutory tax rate	21%	21%	21%	21%
State taxes, net of federal benefit	6%	5.80%	6%	5.80%
Executive compensation	1.60%	1.40%	1.60%	1.40%
Corporate-Owned Life Insurance	(0.50%)	(0.20%)	(0.50%)	(0.20%)
Other permanent differences	0.40%	0.40%	0.40%	0.30%
Prior year tax adjustments	(11.00%)	(27.10%)	(3.70%)	(10.80%)
Worthless stock		(20.20%)		(7.30%)
Capital loss				(6.70%)
Valuation allowance	0.90%	3.10%	1%	1.90%
Equity-based compensation	(0.30%)	(0.60%)	(1.70%)	(1.60%)
Uncertain tax position	4.20%	19.10%	4.40%	6.90%
Tax credits	(8.50%)	(1.30%)	(8.50%)	(1.30%)
Effective tax rate	13.80%	1.40%	20%	9.40%

Stockholders' Equity - Componen

Stockholders' Equity - Components of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	$ 943,325	$ 916,149	$ 917,585	$ 872,845	$ 846,689	$ 853,211	$ 917,585	$ 853,211
Current period other comprehensive (loss) income:
Total current period other comprehensive income (loss)	(951)	(343)	684	(4,053)	3,151	(1,334)	(610)	(2,236)
Balance	976,317	943,325	916,149	893,330	872,845	846,689	976,317	893,330
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	(14,463)		(12,695)	(10,833)		(14,056)	(12,695)	(14,056)
Current period other comprehensive (loss) income:
Other comprehensive (loss) income before reclassifications	4,745			(3,487)			2,877	(82)
Effect of taxes	(758)			(2,227)			(658)	(2,409)
Total current period other comprehensive income (loss)	3,987			(5,714)			2,219	(2,491)
Balance	(10,476)	(14,463)		(16,547)	(10,833)		(10,476)	(16,547)
Change in Fair Value of Interest Rate Hedge Agreements and Other Adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	2,919		810	4,517		5,923	810	5,923
Current period other comprehensive (loss) income:
Other comprehensive (loss) income before reclassifications	(5,099)			4,379			1,161	5,658
Amounts reclassified from accumulated other comprehensive (loss) income	(1,670)			(2,101)			(5,002)	(5,299)
Effect of taxes	1,831			(617)			1,012	(104)
Total current period other comprehensive income (loss)	(4,938)			1,661			(2,829)	255
Balance	(2,019)	2,919		6,178	4,517		(2,019)	6,178
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	(11,544)	(11,201)	(11,885)	(6,316)	(9,467)	(8,133)	(11,885)	(8,133)
Current period other comprehensive (loss) income:
Other comprehensive (loss) income before reclassifications	(354)			892			4,038	5,576
Amounts reclassified from accumulated other comprehensive (loss) income	(1,670)			(2,101)			(5,002)	(5,299)
Effect of taxes	1,073			(2,844)			354	(2,513)
Total current period other comprehensive income (loss)	(951)	(343)	684	(4,053)	3,151	(1,334)	(610)	(2,236)
Balance	$ (12,495)	$ (11,544)	$ (11,201)	$ (10,369)	$ (6,316)	$ (9,467)	$ (12,495)	$ (10,369)

Stockholders' Equity - Compon_2

Stockholders' Equity - Components of Accumulated Other Comprehensive Loss (Parenthetical) (Details) $ in Millions	Sep. 30, 2024 USD ($)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Expects to reclassify net gains related to change in fair value of interest rate hedge agreement from accumulated other comprehensive (loss) income into earnings	$ 1.1

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details)	Sep. 30, 2024 USD ($)
$200 Million Share Repurchase Program
Equity Class Of Treasury Stock [Line Items]
Stock repurchase program, authorized amount	$ 200,000,000

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Repurchase of Shares (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Equity, Class of Treasury Stock [Line Items]
Stock Repurchased During Period, Value	$ 377	$ 12	$ 33,566	$ 22,869
Stock Repurchased During Period, Shares	2,383	91	239,414	225,467
$200 Million Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Stock Repurchased During Period, Value			$ 26,519	$ 18,126
Stock Repurchased During Period, Shares			191,000	180,000
Vesting of RSUs
Equity, Class of Treasury Stock [Line Items]
Stock Repurchased During Period, Value	$ 377	$ 12
Stock Repurchased During Period, Shares	2,383	91
Vesting of RSUs and PSAs
Equity, Class of Treasury Stock [Line Items]
Stock Repurchased During Period, Value			$ 7,047	$ 4,743
Stock Repurchased During Period, Shares			48,414	45,467

Stock-based Compensation - Addi

Stock-based Compensation - Additional Information (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Apr. 04, 2018	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 6.6	$ 5.2	$ 19.3	$ 15.9
Unrecognized compensation expense		$ 34		$ 34
Share-based compensation arrangement by share-based payment award, award vesting period				1 year 6 months
Omnibus Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares grants	2,050,000
Share-based compensation arrangement by share-based payment award, number of shares available for grant		1,018,803		1,018,803

Stock-based Compensation - Sche

Stock-based Compensation - Schedule Of Awards Granted (Details) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Awards Granted	10,302	10,492	127,655	190,525
Employee Stock Awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Awards Granted	672		83,467	113,569
Average Grant Date Fair Value	$ 153.5		$ 152.59	$ 107.29
Cash-Settled RSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Awards Granted	3,012	2,281	37,570	68,745
Average Grant Date Fair Value	$ 153.5	$ 130.47	$ 152.64	$ 110.04
Non-Employee Director Stock Awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Awards Granted	6,618	8,211	6,618	8,211
Average Grant Date Fair Value	$ 135.91	$ 127.81	$ 135.91	$ 127.81

Acquisition and Divestiture - A

Acquisition and Divestiture - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Acquisition and Divestiture [Line Items]
Goodwill	$ 1,221,437		$ 1,219,476
Proceeds from divestiture of a business	1,985	$ 47,151
Gain on divestiture	2,009	$ 4,302
Accrued and other future expenses	$ 85,274		$ 79,129

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Share-based compensation arrangement by share-based payment award, award vesting period			1 year 6 months
Restricted Stock Awards
Antidilutive securities excluded from computation of earnings per share, amount	324	0	190	0
Performance Shares | Initial Performance Vesting Period
Share-based compensation arrangement by share-based payment award, award vesting period			2 years

Earnings Per Share - Schedule o

Earnings Per Share - Schedule of EPS Including Dilutive Effect of Stock Awards (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Earnings Per Share [Abstract]
Net Income	$ 32,679	$ 25,611	$ 27,317	$ 23,740	$ 20,312	$ 16,398	$ 85,607	$ 60,450
Weighted-average number of basic shares outstanding during the period	18,760			18,815			18,752	18,795
Dilutive effect of stock awards	150			159			163	163
Weighted-average number of diluted shares outstanding during the period	18,910			18,974			18,915	18,958
Basic EPS	$ 1.74			$ 1.26			$ 4.57	$ 3.22
Diluted EPS	$ 1.73			$ 1.25			$ 4.53	$ 3.19

Fair Value - Schedule of Financ

Fair Value - Schedule of Financial Instruments Measured at Fair Value on Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Interest Rate Swap | Prepaid Expenses and Other Current Assets
Assets:
Assets, Total	$ 1,674	$ 4,820
Interest Rate Swap | Other Assets
Assets:
Assets, Total		398
Interest Rate Swap | Accrued Expenses and Other Current Liabilities
Liabilities:
Liabilities, Total	564
Interest Rate Swap | Other Long-Term Liabilities
Liabilities:
Liabilities, Total	3,917	4,184
Company Owned Life Insurance Policies | Other Assets
Assets:
Assets, Total	23,160	20,438
Level 2 | Interest Rate Swap | Prepaid Expenses and Other Current Assets
Assets:
Assets, Total	1,674	4,820
Level 2 | Interest Rate Swap | Other Assets
Assets:
Assets, Total		398
Level 2 | Interest Rate Swap | Accrued Expenses and Other Current Liabilities
Liabilities:
Liabilities, Total	564
Level 2 | Interest Rate Swap | Other Long-Term Liabilities
Liabilities:
Liabilities, Total	3,917	4,184
Level 2 | Company Owned Life Insurance Policies | Other Assets
Assets:
Assets, Total	$ 23,160	$ 20,438

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Loss Contingencies [Line Items]
Letters of credit	$ 1.8
Standby Letters of Credit
Loss Contingencies [Line Items]
Letters of credit	1.8	$ 1.8
Letters of credit guarantees	$ 6.5	$ 7.9