Fair Value Measurements - Schedule of Financial Instruments Outstanding Measured at Fair Value on Recurring and Nonrecurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Recurring
Forward contracts	$ (5,000)
Carrying Amount [Member]
Recurring
Forward contracts	(5,026)	$ (28,784)
Non-recurring
Cash and cash equivalents	500,456	664,844
Restricted cash and cash equivalents	99,632	116,801
Debt	(754,392)	(843,883)
Fair value [Member]
Recurring
Forward contracts	(5,026)	(28,784)
Non-recurring
Cash and cash equivalents	500,456	664,844
Restricted cash and cash equivalents	99,632	116,801
Debt	(746,820)	(777,634)
Level 1 [Member]
Non-recurring
Cash and cash equivalents	500,456	664,844
Restricted cash and cash equivalents	99,632	116,801
Level 2 [Member]
Recurring
Forward contracts	(5,026)	(28,784)
Non-recurring
Debt	(693,716)	(707,492)
Level 3 [Member]
Non-recurring
Debt	$ (53,104)	$ (70,142)