Leases - Summary of Components of Lease Costs (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Finance lease costs:
Amortization of right-of-use assets	$ 239
Interest on finance lease liabilities	223
Operating lease costs	540
Short-term lease costs	62
Variable lease costs	152
Total lease costs	$ 1,216

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- Definition

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

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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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