Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss) by Component (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance			$ 3,455,185
Other comprehensive income before reclassifications			782
Change in cash flow hedges reclassed to earnings	$ 172	$ 154	344	$ 829
Net current-period other comprehensive income			1,126
Ending Balance	3,400,213		3,400,213
Gains on Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance			(6,109)
Other comprehensive income before reclassifications			376
Change in cash flow hedges reclassed to earnings			344
Net current-period other comprehensive income			720
Ending Balance	(5,389)		(5,389)
Foreign Currency Items [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance			(174)
Other comprehensive income before reclassifications			406
Change in cash flow hedges reclassed to earnings			0
Net current-period other comprehensive income			406
Ending Balance	232		232
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance			(6,283)
Ending Balance	$ (5,157)		$ (5,157)