Investments in and Advances to Joint Ventures - Summary of Financial Information for Unconsolidated Joint Ventures (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Dec. 31, 2025 |
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| Schedule Of Equity Method Investments [Line Items] | |||||
| Current assets | $ 2,579,109 | $ 2,579,109 | $ 2,683,543 | ||
| Total assets | 5,985,237 | 5,985,237 | 5,769,534 | ||
| Current liabilities | 1,617,116 | 1,617,116 | 1,531,664 | ||
| Total liabilities | 3,237,080 | 3,237,080 | 3,001,862 | ||
| Total joint venture equity | 2,637,648 | 2,637,648 | 2,642,020 | ||
| Investments in and advances to unconsolidated joint ventures | 174,764 | 174,764 | 148,640 | ||
| Revenue | 1,650,548 | $ 1,621,748 | 4,717,591 | $ 4,760,431 | |
| Costs | 1,268,481 | 1,261,893 | 3,682,866 | 3,698,240 | |
| Net income attributable to Parsons Corporation | 54,153 | 64,123 | 91,860 | 185,556 | |
| Equity in earnings of unconsolidated joint ventures | 7,242 | 8,266 | (20,350) | 6,937 | |
| Unconsolidated Joint Ventures | |||||
| Schedule Of Equity Method Investments [Line Items] | |||||
| Current assets | 1,373,495 | 1,373,495 | 1,549,367 | ||
| Noncurrent assets | 411,609 | 411,609 | 439,496 | ||
| Total assets | 1,785,104 | 1,785,104 | 1,988,863 | ||
| Current liabilities | 843,237 | 843,237 | 1,046,970 | ||
| Noncurrent liabilities | 458,554 | 458,554 | 469,833 | ||
| Total liabilities | 1,301,791 | 1,301,791 | 1,516,803 | ||
| Total joint venture equity | 483,313 | 483,313 | 472,060 | ||
| Investments in and advances to unconsolidated joint ventures | 174,764 | 174,764 | $ 148,640 | ||
| Revenue | 599,294 | 608,305 | 1,331,238 | 1,558,656 | |
| Costs | 551,887 | 563,832 | 1,318,855 | 1,476,009 | |
| Net income attributable to Parsons Corporation | 47,407 | 44,473 | 12,383 | 82,647 | |
| Unconsolidated Joint Ventures | |||||
| Schedule Of Equity Method Investments [Line Items] | |||||
| Equity in earnings of unconsolidated joint ventures | $ 7,242 | $ 8,266 | $ (20,350) | $ 6,937 | |
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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold or consumed after one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in equity method investee and investment in and advance to affiliate. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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