Leases - Schedule of Lease Cost and Other Information (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Lease Cost
Operating lease cost	$ 2,688
Short-term lease cost	970
Variable lease cost	348
Total lease cost	4,006
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flow from operating leases	2,696
Right-of-use assets obtained in exchange for new operating lease liabilities	$ 294
Weighted-average remaining lease term-operating leases	9 years
Weighted-average discount rate-operating leases	3.90%