Stockholders' Equity - Schedule of Accumulated Other Comprehensive Income Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, net of tax, Beginning balance			$ 1,580,664
Other comprehensive income (loss), net of tax	$ 11,504	$ (30,937)	17,008	$ (48,130)
Accumulated other comprehensive income, net of tax, Ending balance	1,576,907		1,576,907
Foreign Currency Translation [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, net of tax, Beginning balance			(128,671)
Other comprehensive income (loss) before reclassifications, net of tax			16,989
Other comprehensive income (loss), net of tax			16,989
Accumulated other comprehensive income, net of tax, Ending balance	(111,682)		(111,682)
Unrealized Gains (Losses) on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, net of tax, Beginning balance			(23)
Other comprehensive income (loss) before reclassifications, net of tax			19
Other comprehensive income (loss), net of tax			19
Accumulated other comprehensive income, net of tax, Ending balance	(4)		(4)
Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, net of tax, Beginning balance			(128,694)
Other comprehensive income (loss) before reclassifications, net of tax			17,008
Other comprehensive income (loss), net of tax			17,008
Accumulated other comprehensive income, net of tax, Ending balance	$ (111,686)		$ (111,686)