Summary of Significant Accounting Policies - Leases (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) Option	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Lessee, Lease, Description [Line Items]
Variable lease expense and short-term lease expenses	$ 8,400
Weighted average discount rate	3.90%
Lease expense	$ 24,800	$ 23,400	$ 21,100
Weighted average remaining lease term	8 years 1 month 6 days
Rent paid to related parties	$ 3,700	$ 4,800	$ 4,800
Existence of option to extend	true
Summary of lease asset and liabilities
Lease right-of-use assets	$ 84,073
Lease Liabilities
Other current liabilities	$ 14,016
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other current liabilities
Long-term lease liabilities	$ 72,697
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Long-term lease liabilities
Present Value of Lease Liabilities	$ 86,713
Minimum
Lessee, Lease, Description [Line Items]
Lease term	3 years
Number of options to renew | Option	1
Maximum
Lessee, Lease, Description [Line Items]
Lease term	10 years