Leases - Summary of Future Maturities of Lease and Non-Lease Components (Detail) - USD ($) $ in Thousands		Mar. 31, 2019	Dec. 31, 2018
Operating Leases [Abstract]
Operating Leases, Remainder of 2019		$ 22,128
Operating Leases, 2020		24,839
Operating Leases, 2021		20,773
Operating Leases, 2022		19,205
Operating Leases, 2023		16,817
Operating Leases, Thereafter		33,171
Operating Leases, Total lease liabilities		136,933
Operating Leases, Less: Amount representing interest		(17,667)
Operating Leases, Less: Short-term lease liabilities		(24,154)	$ 0
Operating Leases, Total long-term lease liabilities		95,112	$ 0
Finance Leases [Abstract]
Finance Leases, Remainder of 2019		107
Finance Leases, 2020		85
Finance Leases, 2021		40
Finance Leases, 2022		6
Finance Leases, 2023		0
Finance Leases, Thereafter		0
Finance Leases, Total lease liabilities		238
Finance Leases, Less: Amount representing interest		(11)
Finance Leases, Less: Short-term lease liabilities	[1]	(130)
Finance Leases, Total long-term lease liabilities	[2]	$ 97

[1] Current finance lease liabilities are included in Accrued expenses within the consolidated balance sheets.

[2] Long-term finance lease liabilities are included in Other liabilities within the consolidated balance sheets.