Leases - Other lease disclosures (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Lessee Disclosure [Abstract]
Operating cash flows from finance leases	$ 8,177	$ 8,868
Operating cash flows from operating leases	1,129	1,540
Financing cash flows from finance leases	6,772	6,082
Right-of-use assets obtained in exchange for new operating lease liabilities	0	1,227
Finance Leases
2022	14,949
2023	14,949
2024	14,949
2025	14,949
2026	14,949
Thereafter	25,633
Total lease payments	100,378
Less: imputed interest	(31,502)
Total finance lease liabilities	68,876	75,649
Operating Leases
2022	929
2023	708
2024	234
2025	72
2026	72
Thereafter	940
Total lease payments	2,955
Less: imputed interest	(567)
Total operating lease liabilities	2,388	3,378
Total
2022	15,878
2023	15,657
2024	15,183
2025	15,021
2026	15,021
Thereafter	26,573
Total lease payments	103,333
Less: imputed interest	(32,069)
Present value of lease liabilities	71,264
Lessor Disclosure [Abstract]
Lease income	$ 6,312	$ 6,171

Present value of lessee's discounted obligation for lease payments from finance lease and operating lease.

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Amount of lessee's undiscounted obligation for lease payments for finance lease and operating lease.

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Amount of lessee's undiscounted obligation for lease payments for finance lease and operating lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease and operating lease, due in fourth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease and operating lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease and operating lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Amount of interest paid on finance lease liability.

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Amount of lessee's undiscounted obligation for lease payments for finance lease.

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

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Amount of cash outflow for principal payment on finance lease.

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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