Other Comprehensive Loss - Changes in Accumulated OCI by Component (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	$ 3,455,185
Other comprehensive income (loss) before reclassifications	1,403	$ (104)	$ 8,330
Change in cash flow hedges reclassed to earnings	688	1,173	472
Reclassification adjustment of foreign currency translation			21,755
Reclassification adjustment for realized gains on available-for-sale securities	0	0	(1,416)
Net current-period other comprehensive income (loss)	2,091	1,069	29,141
Ending Balance	3,237,515	3,455,185
Gains and Losses on Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(6,109)	(8,485)	(7,912)
Other comprehensive income (loss) before reclassifications	1,491	1,203	(1,045)
Change in cash flow hedges reclassed to earnings	688	1,173	472
Reclassification adjustment of foreign currency translation			0
Reclassification adjustment for realized gains on available-for-sale securities			0
Net current-period other comprehensive income (loss)	2,179	2,376	(573)
Ending Balance	(3,930)	(6,109)	(8,485)
Foreign Currency Items [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(174)	1,133	(30,624)
Other comprehensive income (loss) before reclassifications	(88)	(1,307)	10,002
Change in cash flow hedges reclassed to earnings	0	0	0
Reclassification adjustment of foreign currency translation			21,755
Reclassification adjustment for realized gains on available-for-sale securities			0
Net current-period other comprehensive income (loss)	(88)	(1,307)	31,757
Ending Balance	(262)	(174)	1,133
Net Unrealized Gains (Losses) on Marketable Securities [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	0	0	2,043
Other comprehensive income (loss) before reclassifications	0	0	(627)
Change in cash flow hedges reclassed to earnings	0	0	0
Reclassification adjustment of foreign currency translation			0
Reclassification adjustment for realized gains on available-for-sale securities			(1,416)
Net current-period other comprehensive income (loss)	0	0	(2,043)
Ending Balance	0	0	0
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(6,283)	(7,352)	(36,493)
Reclassification adjustment of foreign currency translation	0	0	21,800
Ending Balance	$ (4,192)	$ (6,283)	$ (7,352)