Other Comprehensive Loss - Components Of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 2,572,871	$ 2,167,724	$ 1,683,028
Foreign currency translation (loss) gain	(127,521)	206,784	(477,967)
Gain (loss) on derivative instruments, net of tax of $12.7 million, $(22.9) million and $29.1, respectively	36,799	(33,431)	40,598
Pension liability adjustment, net of tax of $0.3 million, $0.4 million and $(1.3) million, respectively	2,463	2,099	(7,554)
Balance	2,333,307	2,572,871	2,167,724
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(376,740)	(584,081)	(106,309)
Foreign currency translation (loss) gain	(127,788)	207,341	(477,772)
Balance	(504,528)	(376,740)	(584,081)
Change in Fair Value of Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	7,167	40,598
Gain (loss) on derivative instruments, net of tax of $12.7 million, $(22.9) million and $29.1, respectively	36,799	(33,431)	40,598
Balance	43,966	7,167	40,598
Pension Plan [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(4,545)	(6,087)	1,662
Foreign currency translation (loss) gain	267	(557)	(195)
Pension liability adjustment, net of tax of $0.3 million, $0.4 million and $(1.3) million, respectively	2,463	2,099	(7,554)
Balance	(1,815)	(4,545)	(6,087)
Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(374,118)	(549,570)	(104,647)
Balance	$ (462,377)	$ (374,118)	$ (549,570)