Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Lessee, Lease, Description [Line Items]
Lease expense	$ 14,271	$ 14,728	$ 27,121	$ 28,255
Short term lease expense	(125)	1,048	217	2,503
Variable lease expense	(424)	2,060	101	2,174
Sublease income	26	(693)	(176)	(1,769)
Total operating lease expense	13,748	17,143	27,263	31,163
Offices
Lessee, Lease, Description [Line Items]
Lease expense	7,487	8,574	13,801	16,914
Short term lease expense	(69)	523	217	1,448
Variable lease expense	4	1,821	13	1,821
Sublease income	26	(693)	(176)	(1,769)
Total operating lease expense	7,448	10,225	13,855	18,414
Data Centers
Lessee, Lease, Description [Line Items]
Lease expense	6,784	6,154	13,320	11,341
Short term lease expense	(56)	525	0	1,055
Variable lease expense	(428)	239	88	353
Sublease income	0	0	0	0
Total operating lease expense	$ 6,300	$ 6,918	$ 13,408	$ 12,749