Derivative Instruments and Hedging Activities - Schedule of Pre-tax Effect of Derivative Financial Instruments on Unaudited Condensed Consolidated Statements of Comprehensive Income (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Derivatives in Cash Flow Hedging Relationships:
(Loss) gain related to effective portion of derivatives recognized in accumulated other comprehensive loss	$ (21,924,000)	$ 1,846,000
Gain (loss) related to effective portion of derivatives reclassified from accumulated other comprehensive loss to interest expense	3,154,000	(2,626,000)
Loss related to ineffective portion of derivatives recognized in other expense (income), net	$ (287,000)	$ 0