Accumulated Other Comprehensive Loss - Amounts Reclassified from AOCI (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Mark-to-Market Loss on Interest Rate Protection Agreements	$ 0	$ 0	$ (11,546)	$ 0
Interest Expense	16,674	17,322	49,679	55,292
Total	(14,496)	(17,426)	(50,373)	(56,253)
Reclassification Out Of Accumulated Other Comprehensive Income | Interest Rate Protection Agreements
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total	1,430	1,221	16,803	4,129
Interest Rate Contract | Reclassification Out Of Accumulated Other Comprehensive Income | Interest Rate Protection Agreements
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest Expense	131	131	393	1,227
Interest Rate Swap | Reclassification Out Of Accumulated Other Comprehensive Income | Interest Rate Protection Agreements
Accumulated Other Comprehensive Income (Loss) [Line Items]
Mark-to-Market Loss on Interest Rate Protection Agreements	0	0	12,990	0
Interest Expense	$ 1,299	$ 1,090	$ 3,420	$ 2,902