Derivative Instruments and Hedging Activities - Additional Information (Detail) (USD $)	3 Months Ended			3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	May 14, 2013 Swap	Mar. 31, 2014 Interest Rate Risk [Member]	Mar. 31, 2013 Interest Rate Risk [Member]	Mar. 31, 2014 Interest Rate Swaps [Member] Swap	May 14, 2013 Interest Rate Swaps [Member] Swap	Aug. 23, 2012 Interest Rate Swaps [Member] Swap	Mar. 31, 2014 Not Designated as Hedge Accounting Relationships [Member]	Dec. 31, 2013 Not Designated as Hedge Accounting Relationships [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives outstanding									$ 0	$ 0
Notional amount interest rate swap (In USD)						1,000,000,000	550,000,000	550,000,000
Number of outstanding interest rate derivatives						3	2	2
Number of restructured interest rate swaps			2
Reclassified as an increase to interest expense	2,921,000
Ineffective portion of change in fair value of derivatives recognized in earnings				0	0
Tax benefit on unrealized loss on derivatives	123,000
Termination value of derivatives in net liability position	264,000
Collateral posted relating to credit risk-related contingent features	$ 0