Commitments and Contingencies - Commitments for Minimum Rentals under Non-cancelable Leases (Detail) $ in Thousands	Dec. 31, 2018 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Operating Leases, 2019	$ 9,940
Operating Leases, 2020	10,601
Operating Leases, 2021	10,502
Operating Leases, 2022	8,965
Operating Leases, 2023	8,409
Operating Leases, Thereafter	86,797
Operating Leases, Minimum Payments, Total	135,214
Lease Obligation, 2019	956
Lease Obligation, 2020	967
Lease Obligation, 2021	0
Lease Obligation, 2022	0
Lease Obligation, 2023	0
Lease Obligation, Thereafter	0
Lease Obligation, Minimum Payments, Total	$ 1,923

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

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