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v3.19.3

Segment Reporting Revenue by Customer Type (details) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Revenue from External Customer [Line Items] |  |  |  |
Revenues | $ 1,002.7 | $ 906.4 | $ 2,898.7 | $ 2,470.1
Department of Defense and Intelligence Agencies |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |
Revenues | 112.6 | 101.5 | 316.2 | 197.0
Federal Civilian |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |
Revenues | 82.0 | 52.6 | 213.5 | 103.6
Other |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |
Revenues | 11.5 | 9.9 | 35.0 | 18.5
ECS |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |
Revenues | $ 206.1 | $ 164.0 | $ 564.7 | $ 319.1

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