Segment Information - Summary of Adjusted EBITDA Business Segment Information (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Segment Reporting Information [Line Items] | ||||
| Revenue | $ 1,650,548 | $ 1,621,748 | $ 4,717,591 | $ 4,760,431 |
| Direct cost of contracts | (1,268,481) | (1,261,893) | (3,682,866) | (3,698,240) |
| Selling, general and administrative expenses | (100,946) | (92,239) | (292,459) | (275,542) |
| Equity in earnings of unconsolidated joint ventures | 7,242 | 8,266 | (20,350) | 6,937 |
| Other segment items | (133,983) | (135,578) | (401,861) | (386,298) |
| Adjusted EBITDA attributable to Parsons Corporation | 154,380 | 140,304 | 320,055 | 407,288 |
| Reconciliation: Segment Adjusted EBITDA to Net Income Attributable to Parsons Corporation | ||||
| Adjusted EBITDA attributable to noncontrolling interests | 13,463 | 17,833 | 40,937 | 48,756 |
| Depreciation and amortization | (34,118) | (29,849) | (106,681) | (85,844) |
| Interest expense, net | (15,437) | (11,696) | (45,445) | (33,301) |
| Income tax expense | (20,446) | (16,035) | (40,755) | (53,702) |
| Equity-based compensation expense | (11,518) | (11,568) | (31,049) | (30,190) |
| Transaction related costs | (16,180) | (5,074) | (17,493) | (13,910) |
| Restructuring expense | (292) | (2,653) | ||
| Other | (2,733) | (1,829) | 12,588 | (2,374) |
| Net income including noncontrolling interests | 67,411 | 81,794 | 132,157 | 234,070 |
| Net income attributable to noncontrolling interests | (13,258) | (17,671) | (40,297) | (48,514) |
| Net income attributable to Parsons Corporation | 54,153 | 64,123 | 91,860 | 185,556 |
| Federal Solution Segment | ||||
| Segment Reporting Information [Line Items] | ||||
| Revenue | 804,553 | 788,607 | 2,323,769 | 2,436,628 |
| Direct cost of contracts | (621,008) | (612,500) | (1,874,091) | (1,917,218) |
| Selling, general and administrative expenses | (52,570) | (47,980) | (147,818) | (136,604) |
| Equity in earnings of unconsolidated joint ventures | 1,787 | 986 | 5,030 | 983 |
| Other segment items | (58,636) | (56,612) | (174,997) | (168,684) |
| Adjusted EBITDA attributable to Parsons Corporation | 74,126 | 72,501 | 131,893 | 215,105 |
| Critical Infrastructure | ||||
| Segment Reporting Information [Line Items] | ||||
| Revenue | 845,995 | 833,141 | 2,393,822 | 2,323,803 |
| Direct cost of contracts | (647,473) | (649,393) | (1,808,775) | (1,781,022) |
| Selling, general and administrative expenses | (48,376) | (44,259) | (144,641) | (138,938) |
| Equity in earnings of unconsolidated joint ventures | 5,455 | 7,280 | (25,380) | 5,954 |
| Other segment items | (75,347) | (78,966) | (226,864) | (217,614) |
| Adjusted EBITDA attributable to Parsons Corporation | $ 80,254 | $ 67,803 | $ 188,162 | $ 192,183 |
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- Definition Adjusted EBITDA attributable to noncontrolling interests. No definition available.
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- Definition Adjusted EBITDA attributable to parent. No definition available.
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- Definition Equity-based compensation income (expense). No definition available.
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- Definition Other reconciliation from net income to adjusted EBITDA. No definition available.
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- Definition Reconciliation from net income to adjusted EBITDA. No definition available.
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- Definition Restructuring income (expense). No definition available.
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- Definition Significant segment expense. No definition available.
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- Definition Transaction related costs. No definition available.
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- Definition The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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 income (loss) for proportionate share of equity method investee's income (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of interest income (expense) classified as operating. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of Net Income (Loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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/disclosureRef
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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/disclosureRef
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