Leases - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) ft²	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Operating Leased Assets [Line Items]
Operating lease, right of use asset	$ 85,538	$ 0
Operating lease, liability	113,026
Total rental expenses under operating lease agreements		$ 18,900	$ 19,800
UNITED STATES
Operating Leased Assets [Line Items]
Operating lease, right of use asset	71,000
Operating lease, liability	97,500
UNITED STATES | Northern Virginia Office Space
Operating Leased Assets [Line Items]
Operating lease, right of use asset	66,900
Operating lease, liability	$ 93,300
Area of office space | ft²	214,000
Lease term expiration date	Dec. 31, 2030
Lease option to extend, description	option for the Company to extend the term for an additional five or 10 consecutive years
Non-US
Operating Leased Assets [Line Items]
Operating lease, right of use asset	$ 14,500
Operating lease, liability	$ 15,500
Minimum | UNITED STATES | Northern Virginia Office Space
Operating Leased Assets [Line Items]
Lease extension term	5 years
Maximum | UNITED STATES | Northern Virginia Office Space
Operating Leased Assets [Line Items]
Lease extension term	10 years