Commitments and Contingencies - Leases Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) lease	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Lessee, Lease, Description [Line Items]
Lease expense	$ 13,509	$ 12,984
Number of leases abandoned | lease	14
Lease expense for operating leases	$ 13,500	$ 13,000	$ 10,900
Transition To Employee Centric Model
Lessee, Lease, Description [Line Items]
Lease restructuring expenses	24,300
Other non-recurring expense	$ 5,100
Minimum
Lessee, Lease, Description [Line Items]
Finance lease initial terms	1 year
Finance leases remaining lease term	1 year
Operating leases remaining lease term	1 year
Maximum
Lessee, Lease, Description [Line Items]
Finance lease initial terms	12 years
Finance leases remaining lease term	5 years
Operating leases remaining lease term	5 years