Components of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at the beginning of the period	$ 1,407,884
Other comprehensive income (loss) before reclassifications	(57,265)	$ (2,190)	$ (536)
Net losses (gains) reclassified from accumulated other comprehensive loss	(322)	(73)	302
Total other comprehensive income (loss)	(57,587)	(2,263)	(234)
Balance at the end of the period	1,232,466	1,407,884
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at the beginning of the period	(4,500)	(2,119)	(1,590)
Other comprehensive income (loss) before reclassifications	(1,528)	(2,381)	(529)
Net losses (gains) reclassified from accumulated other comprehensive loss	0	0	0
Total other comprehensive income (loss)	(1,528)	(2,381)	(529)
Balance at the end of the period	(6,028)	(4,500)	(2,119)
Unrealized Net Gains (Losses) on Available for Sale Securities [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at the beginning of the period	0	140	124
Other comprehensive income (loss) before reclassifications	(56,420)	0	16
Net losses (gains) reclassified from accumulated other comprehensive loss	0	(140)	0
Total other comprehensive income (loss)	(56,420)	(140)	16
Balance at the end of the period	(56,420)	0	140
Derivatives Qualifying as Cash Flow Hedges [Member] | Interest Rate Swap [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at the beginning of the period	0	0	(279)
Other comprehensive income (loss) before reclassifications	0	0	(23)
Net losses (gains) reclassified from accumulated other comprehensive loss	0	0	302
Total other comprehensive income (loss)	0	0	279
Balance at the end of the period	0	0	0
Derivatives Qualifying as Cash Flow Hedges [Member] | Foreign Exchange Contract [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at the beginning of the period	258	0	0
Other comprehensive income (loss) before reclassifications	683	191	0
Net losses (gains) reclassified from accumulated other comprehensive loss	(322)	67	0
Total other comprehensive income (loss)	361	258	0
Balance at the end of the period	619	258	0
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at the beginning of the period	(4,242)	(1,979)	(1,745)
Balance at the end of the period	$ (61,829)	$ (4,242)	$ (1,979)