Leases - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Lease Cost
Amortization of leased assets	$ 1,344	$ 1,189	$ 2,688	$ 2,378
Interest on lease liabilities	2,217	2,372	4,434	4,744
Operating lease cost:	272	883	795	1,766
Total leased cost	$ 3,833	$ 4,444	$ 7,917	$ 8,888
Weighted-average remaining lease term (in years)
Finance leases	8 years 7 months 2 days		8 years 7 months 2 days		8 years 10 months 2 days
Operating leases	7 years 4 months 2 days		7 years 4 months 2 days		7 years 4 months 20 days
Weighted-average discount rate:
Finance leases	11.05%		11.05%		11.05%
Operating leases	4.62%		4.62%		5.12%