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v3.22.0.1

Segment Reporting - Federal Government Segment Revenues by Customer Type (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2021 | Sep. 30, 2021 | Jun. 30, 2021 | Mar. 31, 2021 | Dec. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues | $ 1,053.8 | $ 1,073.8 | $ 974.9 | $ 907.0 | $ 900.4 | $ 904.4 | $ 831.9 | $ 865.4 | $ 4,009.5 | $ 3,502.1 | $ 3,415.6
Federal Government |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 1,082.4 | 1,004.2 | 798.2
Federal Government | Department of Defense and Intelligence Agencies |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 589.7 | 558.5 | 453.9
Federal Government | Federal Civilian |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 421.8 | 370.6 | 293.6
Federal Government | Other |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | $ 70.9 | $ 75.1 | $ 50.7

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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. 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