Segment Information - Additional Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) Segment	Jun. 30, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | Segment			4
Revenues	$ 598,806	$ 575,219	$ 1,297,302	$ 1,194,499
London, Bermuda and Cayman Islands
Segment Reporting Information [Line Items]
Revenues	$ 9,200	$ 4,600	$ 16,100	$ 8,000