Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Finance Lease Cost
Amortization of right-of-use asset	$ 185	$ 172	$ 527	$ 527
Interest on lease liabilities	8	11	24	39
Total finance lease cost	193	183	551	566
Operating lease cost	10,072	11,087	30,142	33,157
Short-term lease cost	2,743	2,126	9,379	5,846
Total lease cost	$ 13,008	$ 13,396	$ 40,072	$ 39,569