Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Operating lease cost:
Fixed	$ 73,624	$ 72,714
Variable	8,532	8,333
Impairment of ROU Asset	6,003	27,104
Total Operating lease cost	88,159	108,151
Sublease income	16,437	12,590
Finance lease cost:
Amortization of right-of-use assets	11,536	12,565
Interest on lease liabilities	432	661
Total Finance lease cost	$ 11,968	$ 13,226

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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- Definition

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 loss from impairment of right-of-use asset from operating lease.

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Amount of sublease income excluding finance and operating lease expense.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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Finance Lease, Cost

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