Summary of Future Minimum Lease Payments Under Non-Cancelable Operating Leases Recognized Under Topic 842 (Detail) $ in Thousands	Mar. 31, 2019 USD ($)
Maturity of lease liability
2019 (April - December)	$ 8,061
2020	11,395
2021	12,558
2022	10,737
2023	10,877
Thereafter	20,484
Total minimum lease payments	74,112
Less: imputed interest	(15,183)
Total operating lease liabilities	58,929
Included in the condensed consolidated balance sheet:
Current portion of lease liabilities within other current liabilities	$ 6,764
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilitiesCurrent
Lease liabilities	$ 52,165
Total operating lease liabilities	$ 58,929