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Leases - Other Lease Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Lessee
Operating cash flows from finance leases			$ 4,180	$ 4,516
Operating cash flows from operating leases			539	950
Financing cash flows from finance leases			3,295	2,959
Right-of-use assets obtained in exchange for new operating lease liabilities			0	1,227
Finance Leases
2021	$ 7,474		7,474
2022	14,949		14,949
2023	14,949		14,949
2024	14,949		14,949
2025	14,949		14,949
Thereafter	40,582		40,582
Total lease payments	107,852		107,852
Less: imputed interest	(35,499)		(35,499)
Total finance lease liabilities	72,353		72,353		$ 75,649
Operating Leases
2021	580		580
2022	929		929
2023	708		708
2024	234		234
2025	72		72
Thereafter	1,011		1,011
Total lease payments	3,534		3,534
Less: imputed interest	(650)		(650)
Total operating lease liabilities	2,884		2,884		$ 3,378
Total
2021	8,054		8,054
2022	15,878		15,878
2023	15,657		15,657
2024	15,183		15,183
2025	15,021		15,021
Thereafter	41,593		41,593
Total lease payments	111,386		111,386
Less: imputed interest	(36,149)		(36,149)
Present value of lease liabilities	75,237		75,237
Lessor
Lease income	$ 1,606	$ 1,542	$ 3,203	$ 3,090