Leases - Summary of Components of Lease Cost (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Leases [Abstract]
Operating lease cost	$ 19,966
Finance lease cost:
Amortization of right-of-use assets	935
Interest on lease liabilities	148
Variable lease cost	4,667
Short-term lease cost	8,118
Total lease cost	$ 33,834

No definition available.

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- Definition

Amount of interest expense on finance lease liability.

+ References

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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.

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- References

No definition available.

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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

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

+ 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.

+ References

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