Derivative Instruments and Hedging Activities - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Derivative [Line Items]
Aggregate fair value of net liability position	$ 5,700,000
Collateral posted with counterparties	27,900,000
Interest Rate Swaps [Member]
Derivative [Line Items]
Accumulated net after-tax losses related to effective cash flow hedges	9,000,000		6,300,000
Estimated amount of interest rate derivatives to be reclassified to interest expense	8,400,000
Recognized a net reduction to interest expense	$ 100,000	$ 142,000