Derivative Instruments and Hedging Activities - Additional Information (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($) Swap	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) Swap	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)	Jun. 30, 2015 USD ($) Swap
Derivative Instruments, Gain (Loss) [Line Items]
Loss related to ineffective portion of derivatives recognized in other (income) expense, net		$ (1,000)	$ (1,000)	$ (288,000)
Reclassified as an increase to interest expense, expected during the next 12 months	$ 15,112,000		15,112,000
Unrealized gain (loss) on derivatives, tax (benefit) and expense	1,003,000	$ (5,907,000)	(10,497,000)	$ (8,799,000)
Termination value of derivatives in a net liability position	44,824,000		44,824,000
Collateral posted relating to credit risk-related contingent features	0		0
Forward Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount of interest rate swap						$ 1,000,000,000
Number of interest rate swaps held | Swap						5
Combined Interest Rate Cash Flow Hedges, All Swaps [Member] | Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount of interest rate swap	$ 1,250,000,000		$ 1,250,000,000
Number of interest rate swaps matured | Swap	4		4
Combined Interest Rate Cash Flow Hedges, All Swaps [Member] | Forward Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount of interest rate swap	$ 1,000,000,000		$ 1,000,000,000
Number of interest rate swaps held | Swap	5		5
Not Designated as Hedge Accounting Relationships [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives outstanding	$ 0		$ 0		$ 0