Income Taxes - Summary of Components of Deferred Tax Balances (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets:
Tax credit carry forward	$ 4,806	$ 5,164
Depreciation and amortization	3,765	3,777
Share-based compensation	10,385	8,099
Accrued employee costs and other expenses	5,130	3,079
Net operating loss carry forwards	1,856	3,746
Unrealized exchange loss	2,099	1,136
Deferred rent	1,307	1,292
Others	484	62
Deferred tax assets	29,832	26,355
Valuation allowance	(454)	(595)
Deferred tax assets	29,378	25,760
Deferred tax liabilities:
Unrealized exchange gain	1,414	848
Intangible assets	13,165	11,163
Deferred tax liabilities:	14,579	12,011
Net deferred tax assets	$ 14,799	$ 13,749