Changes in Accumulated Other Comprehensive Income (loss) by Component Net of Taxes (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]
Balance			$ 3,226,737
Other comprehensive (loss) income before reclassifications			(2,270)	$ (16,896)
Amounts reclassified from accumulated other comprehensive income (loss)			1,190	569
Net current-period other comprehensive income (loss)	$ (8,417)	$ (8,497)	(1,080)	(16,327)
Balance	3,142,073		3,142,073
Available-for-sale securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			137	133
Other comprehensive (loss) income before reclassifications			204	(2)
Amounts reclassified from accumulated other comprehensive income (loss)			58	1
Net current-period other comprehensive income (loss)			262	(1)
Balance	399	132	399	132
Derivative instruments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			671	(6,781)
Other comprehensive (loss) income before reclassifications			(456)	(17,223)
Amounts reclassified from accumulated other comprehensive income (loss)			1,117	2,593
Net current-period other comprehensive income (loss)			661	(14,630)
Balance	1,332	(21,411)	1,332	(21,411)
Change related to pension liability
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			(6,810)	(4,195)
Amounts reclassified from accumulated other comprehensive income (loss)			15	(2,025)
Net current-period other comprehensive income (loss)			15	(2,025)
Balance	(6,795)	(6,220)	(6,795)	(6,220)
Cumulative Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			9,293	(1,803)
Other comprehensive (loss) income before reclassifications			(2,018)	329
Net current-period other comprehensive income (loss)			(2,018)	329
Balance	7,275	(1,474)	7,275	(1,474)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			3,291	(12,646)
Balance	$ 2,211	$ (28,973)	$ 2,211	$ (28,973)