Supplemental Disclosure to Statements of Cash Flows (Tables)

12 Months Ended

Dec. 31, 2011

Supplemental Disclosure to Statements of Cash Flows [Abstract]

Supplemental Disclosure to Statements of Cash Flows

	2011		2010		2009
Write-off of fully depreciated/amortized property and deferred costs	$	127,005	$	48,373	$	76,714
Assumption of mortgage loans	—		2,833		—
Equity contribution from consolidated joint venture partner	3,500		—		—
Issuance of preferred units	16,597		—		—