Leases - Components of Lease Expense (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Operating lease cost:
Fixed	$ 14,797
Variable	1,578
Total Operating lease cost	16,375
Finance lease cost:
Amortization of right-of-use assets	2,970
Interest on lease liabilities	186
Total Finance lease cost	3,156
Sublease income	$ 2,560

Amount of interest expense on finance lease liability.

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- Definition

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

+ References

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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- References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

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- Definition

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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- Definition

Finance Lease, Cost

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