Leases - Schedule of 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:
Total	$ 3,554	$ 4,232	$ 11,005	$ 20,408
Occupancy/Equipment expense
Lessee, Lease, Description [Line Items]
Operating lease cost	2,995	3,952	9,388	19,786
Occupancy expense
Finance lease cost:
Amortization of right-of-use assets	593	311	1,714	733
Sub-lease income	(142)	(129)	(420)	(378)
Interest expense
Finance lease cost:
Interest on lease liabilities	$ 108	$ 98	$ 323	$ 267

Finance lease costs.

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Amount of interest expense on finance lease liability.

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Amount of amortization expense attributable to right-of-use asset from finance lease.

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Amount of lease cost recognized by lessee for lease contract.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Amount of sublease income excluding finance and operating lease expense.

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