Investments in Joint Ventures - Condensed Combined Statements of Operations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of Equity Method Investments [Line Items]
Total Revenues	$ 73,960	$ 71,454	$ 72,376	$ 71,146	$ 71,525	$ 67,313	$ 68,909	$ 67,696	$ 288,936	$ 275,443	$ 263,826
Expenses:
Property Expenses and Other									95,104	88,605	89,772
Impairment of Real Estate									2,652	1,101	(2,079)
Depreciation and Other Amortization									98,824	100,683	102,485
Amortization of Interest Rate Protection Agreements									68,857	77,794	95,103
Discontinued Operations:
Loss Attributable to Discontinued Operations									977	3,380	3,888
Gain on Sale of Real Estate									32,657	12,758	18,814
Gain on Sale of Real Estate									1,030	3,777	1,370
Net Income (Loss)	22,430	8,738	11,393	(1,128)	(2,371)	9,193	(10,344)	1,104	41,433	(2,418)	(8,962)
Equity in Income of Joint Ventures	17	72	27	20	1,403	28	37	91	136	1,559	980
Corporate Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Total Revenues									3,433	3,371	3,411
Expenses:
Property Expenses and Other									1,070	1,096	1,226
Depreciation and Other Amortization									931	764	836
Amortization of Interest Rate Protection Agreements									1,532	1,633	1,643
Total Expenses									3,533	3,493	3,705
Discontinued Operations:
Loss Attributable to Discontinued Operations									(1,300)	(1,607)	(1,587)
Gain on Sale of Real Estate									513	4,974	3,137
(Loss) Income from Discontinued Operations									(787)	3,367	1,550
Net Income (Loss)									(887)	3,245	1,256
Equity in Income of Joint Ventures									$ 136	$ 1,559	$ 980