Accumulated Other Comprehensive Loss - Amounts Reclassified from AOCI (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Mark-to-Market Loss on Interest Rate Protection Agreements	$ 1,444	$ 0	$ (11,546)	$ 0
Interest Expense	16,363	18,924	33,005	37,970
Total	(13,453)	(19,679)	(35,877)	(38,827)
Reclassification Out Of Accumulated Other Comprehensive Income | Interest Rate Protection Agreements
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total	1,195	1,547	15,373	2,908
Interest Rate Contract | Reclassification Out Of Accumulated Other Comprehensive Income | Interest Rate Protection Agreements
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest Expense	131	468	262	1,096
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	$ 1,064	$ 1,079	$ 2,121	$ 1,812