Segment Information - Financial Information by Major Geographic Area (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue:
Total revenue	$ 415,435	$ 1,302,736	$ 1,237,324
Long-lived assets:
Total long-lived assets	507,646	546,020	376,757
Domestic Plans
Revenue:
Total revenue	290,541	873,213	850,839
Long-lived assets:
Total long-lived assets	173,790	205,399	182,140
EMEA
Revenue:
Total revenue	56,656	218,404	202,990
Long-lived assets:
Total long-lived assets	56,996	63,582	48,553
CA
Revenue:
Total revenue	68,238	211,119	183,495
Long-lived assets:
Total long-lived assets	$ 276,860	$ 277,039	$ 146,064