Supplemental Information to Statement of Cash Flows - Cash Flow Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Supplemental Cash Flow Information [Line Items]
Interest Expense Capitalized in Connection with Development Activity	$ 380	$ 754
Supplemental Schedule of Non-cash Investing and Financing Activities:
Distributions Payable	11,921
Exchange of Limited Partnership Units for General Partnership Units:
Conversion of Limited Partner Units to General Partner Units	0	0
Assumption of Liabilities in Connection with the Acquisition of Real Estate	138	0
Accounts Payable Related to Construction in Progress and Additions to Investment in Real Estate	11,657	11,353
Write-off of Fully Depreciated Assets	(8,210)	(10,348)
General Partner Units
Exchange of Limited Partnership Units for General Partnership Units:
Conversion of Limited Partner Units to General Partner Units	1,279	0
Limited Partner Units
Exchange of Limited Partnership Units for General Partnership Units:
Conversion of Limited Partner Units to General Partner Units	(1,279)	0
General and Limited Partner Units
Supplemental Schedule of Non-cash Investing and Financing Activities:
Distributions Payable	11,921	9,536
Preferred Stock [Member]
Supplemental Schedule of Non-cash Investing and Financing Activities:
Distributions Payable	$ 0	$ 4,289