Employee Benefit Plans - Net Gratuity Cost (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Service cost	$ 1,601	$ 1,638	$ 1,523
Interest cost	599	550	559
Expected return on plan assets	(416)	(385)	(172)
Actuarial loss	90	211	149
Net gratuity cost	$ 1,874	$ 2,014	$ 2,059