Leases - Summary of minimum future rental payments required (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Operating Leases
2021	$ 11,263
Year 1	14,883	$ 14,695
Year 2	9,076	14,558
Year 3	7,094	8,746
Year 4	7,136	6,759
Year 5		6,796
Thereafter	116,918
Thereafter		116,660
Total undiscounted rental payments	166,370	168,214
Less imputed interest	(93,195)	(94,375)
Total lease liabilities	$ 73,175	$ 73,839
Weighted average remaining lease term, operating leases	34 years 6 months	34 years 6 months
Weighted average incremental borrowing rate, operating leases	7.70%	7.70%
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Lease liabilities	Lease liabilities
Finance Leases
2021	$ 10,785
Year 1	2,762	$ 10,785
Year 2	344	2,762
Year 3	3,085	344
Year 4	0	3,085
Year 5		0
Thereafter	0
Thereafter		0
Total undiscounted rental payments	16,976	16,976
Less imputed interest	(1,151)	(599)
Total lease liabilities	$ 15,825	$ 16,377
Weighted average remaining lease term, finance leases	10 months 24 days	1 year 1 month 6 days
Weighted average incremental borrowing rate, finance leases	3.70%	3.70%
Finance Lease, Liability, Statement of Financial Position [Extensible List]	Lease liabilities	Lease liabilities

Finance Lease, Liability, to be Paid, after Year Four

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- Definition

Lessee, Operating Lease, Liability, to be Paid, after Year Four

+ References

No definition available.

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No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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- Definition

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).

+ References

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- Definition

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).

+ References

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- Definition

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).

+ References

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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).

+ References

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- Definition

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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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in remainder of current fiscal year.

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-Publisher FASB
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-SubTopic 20
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-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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- Definition

Indicates line item in statement of financial position that includes finance lease liability.

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- Definition

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

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- Definition

Weighted average discount rate for finance lease calculated at point in time.

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- Definition

Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

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

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- Definition

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).

+ References

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

+ References

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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 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 operating 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).

+ References

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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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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

+ References

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- Definition

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

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No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Indicates line item in statement of financial position that includes operating lease liability.

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Namespace Prefix:	us-gaap_
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- Definition

Weighted average discount rate for operating lease calculated at point in time.

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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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