Goodwill - Summary of Changes in Carrying Value of Goodwill by Reporting Segment (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Goodwill [Line Items]
Beginning Balance	$ 1,047,425
Foreign Exchange	(3,411)
Ending Balance	1,044,014
Federal Solutions
Goodwill [Line Items]
Beginning Balance	975,405
Foreign Exchange	0
Ending Balance	975,405
Critical Infrastructure
Goodwill [Line Items]
Beginning Balance	72,020
Foreign Exchange	(3,411)
Ending Balance	$ 68,609

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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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.

+ References

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