Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Operating Leases
Amortization of ROU Assets	$ 98		$ 107
Interest on Lease Liabilities	13		14
Operating lease cost	6,379	$ 6,127	18,927	$ 18,524
Short-term lease cost	974	1,754	3,597	5,289
Variable lease cost	1,192	1,224	3,773	4,301
Total lease cost	8,656	9,105	26,418	28,114
Operating cash flows from operating leases	6,777	14,011	14,259	22,464
Operating cash flows from finance leases	396		580
Financing cash flows from finance leases	14		15
ROU assets obtained in exchange for lease liabilities	287	$ 253	7,759	$ 4,610
ROU assets obtained in exchange for finance lease liabilities	$ 1,904		$ 2,761
Weighted-average remaining lease term (in years)	18 years 10 months 24 days		18 years 10 months 24 days
Weighted-average discount rate	6.89%		6.89%
Weighted-average remaining finance lease term (in years)	3 years 9 months 7 days		3 years 9 months 7 days
Weighted-average discount rate	3.99%		3.99%