Derivative Financial Instruments - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Derivative [Line Items]
Interest Expense	$ 7,343,000	$ 8,457,000
Estimated payments to be made under interest rate swaps	5,500,000
Estimated payments to be made under interest rate swaps, assets	580,000		794,000
Fair value of interest rate swap agreements	9,233,000		7,523,000
Net termination value	8,700,000
Reclassification Out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Derivative [Line Items]
Interest Expense	1,400,000	1,400,000
Interest Rate Swap [Member]
Derivative [Line Items]
Notional amount	$ 325,000,000