Business Segments - Schedule of Results of Operations by Business Segment (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2026 |
Mar. 31, 2025 |
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| Financial information for each of the Company's business segments | ||||
| Revenue | $ 1,305,967 | $ 1,361,786 | $ 2,651,013 | $ 2,764,461 |
| Cost of revenue | 963,703 | 1,022,965 | 1,990,079 | 2,124,083 |
| Gross profit | 342,264 | 338,821 | 660,934 | 640,378 |
| Other segment items | 174,055 | 161,236 | 335,086 | 314,727 |
| Segment operating income/(loss) | 168,209 | 177,585 | 325,848 | 325,651 |
| Divestiture-related gains/(charges) | 8,985 | (39,343) | ||
| Amortization of intangible assets | (20,298) | (22,996) | (40,598) | (46,031) |
| Operating income | 148,487 | 152,968 | 294,697 | 239,755 |
| Depreciation and amortization: | 12,328 | 9,440 | 25,217 | 17,895 |
| Operating Segments | U.S. Federal Services | ||||
| Financial information for each of the Company's business segments | ||||
| Revenue | 753,143 | 777,927 | 1,539,744 | 1,558,582 |
| Cost of revenue | $ 527,698 | $ 575,869 | $ 1,099,364 | $ 1,183,209 |
| Cost of revenue (as a percent) | 70.10% | 74.00% | 71.40% | 75.90% |
| Gross profit | $ 225,445 | $ 202,058 | $ 440,380 | $ 375,373 |
| Gross profit (as a percent) | 29.90% | 26.00% | 28.60% | 24.10% |
| Other segment items | $ 92,741 | $ 83,076 | $ 177,943 | $ 157,291 |
| Other segment items (as a percent) | 12.30% | 10.70% | 11.60% | 10.10% |
| Segment operating income/(loss) | $ 132,704 | $ 118,982 | $ 262,437 | $ 218,082 |
| Segment operating income/(loss) (as a percent) | 17.60% | 15.30% | 17.00% | 14.00% |
| Depreciation and amortization: | $ 7,300 | $ 3,677 | $ 14,415 | $ 6,528 |
| Depreciation and amortization (as a percent) | 1.00% | 0.50% | 0.90% | 0.40% |
| Operating Segments | U.S. Services | ||||
| Financial information for each of the Company's business segments | ||||
| Revenue | $ 415,754 | $ 442,350 | $ 831,002 | $ 894,600 |
| Cost of revenue | $ 315,245 | $ 330,580 | $ 646,099 | $ 687,826 |
| Cost of revenue (as a percent) | 75.80% | 74.70% | 77.70% | 76.90% |
| Gross profit | $ 100,509 | $ 111,770 | $ 184,903 | $ 206,774 |
| Gross profit (as a percent) | 24.20% | 25.30% | 22.30% | 23.10% |
| Other segment items | $ 61,919 | $ 57,963 | $ 117,027 | $ 112,121 |
| Other segment items (as a percent) | 14.90% | 13.10% | 14.10% | 12.50% |
| Segment operating income/(loss) | $ 38,590 | $ 53,807 | $ 67,876 | $ 94,653 |
| Segment operating income/(loss) (as a percent) | 9.30% | 12.20% | 8.20% | 10.60% |
| Depreciation and amortization: | $ 4,161 | $ 4,161 | $ 8,383 | $ 7,972 |
| Depreciation and amortization (as a percent) | 1.00% | 0.90% | 1.00% | 0.90% |
| Operating Segments | Outside the U.S. | ||||
| Financial information for each of the Company's business segments | ||||
| Revenue | $ 137,070 | $ 141,509 | $ 280,267 | $ 311,279 |
| Cost of revenue | $ 120,760 | $ 116,516 | $ 244,616 | $ 253,048 |
| Cost of revenue (as a percent) | 88.10% | 82.30% | 87.30% | 81.30% |
| Gross profit | $ 16,310 | $ 24,993 | $ 35,651 | $ 58,231 |
| Gross profit (as a percent) | 11.90% | 17.70% | 12.70% | 18.70% |
| Other segment items | $ 19,395 | $ 20,197 | $ 40,116 | $ 45,315 |
| Other segment items (as a percent) | 14.10% | 14.30% | 14.30% | 14.60% |
| Segment operating income/(loss) | $ (3,085) | $ 4,796 | $ (4,465) | $ 12,916 |
| Segment operating income/(loss) (as a percent) | (2.30%) | 3.40% | (1.60%) | 4.10% |
| Depreciation and amortization: | $ 867 | $ 1,602 | $ 2,419 | $ 3,395 |
| Depreciation and amortization (as a percent) | 0.60% | 1.10% | 0.90% | 1.10% |
| Segment Reconciling Items | ||||
| Financial information for each of the Company's business segments | ||||
| Divestiture-related gains/(charges) | $ (1,002) | $ 8,985 | $ (39,343) | |
| Other | $ 576 | (619) | 462 | (522) |
| Amortization of intangible assets | $ (20,298) | $ (22,996) | $ (40,598) | $ (46,031) |
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- Definition Segment Cost of Revenue as Percent of Segment Revenue No definition available.
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- Definition Segment Depreciation and Amortization as Percent of Segment Revenue No definition available.
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- Definition Represents segment gross profit expressed as a percentage of segment revenues. No definition available.
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- Definition Segment Operating Income (Loss) No definition available.
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- Definition Represents segment operating income expressed as a percentage of segment revenues. No definition available.
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- Definition Segment Other Expense as Percent of Segment Revenue No definition available.
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The aggregate cost of goods produced and sold and services rendered during the reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The net result for the period of deducting operating expenses from operating revenues. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The net amount of other operating income and expenses, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operations. No definition available.
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- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- 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. No definition available.
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- Definition Amount of other expense (income) and loss (gain) calculated as difference between segment revenue and separately disclosed expense category to arrive at segment profit (loss). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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