Real Estate Investments (Tables)

12 Months Ended

Dec. 31, 2011

Real Estate [Abstract]

Gross carrying value of rental properties

	December 31,
	2011		2010
Land	$	677,891	$	697,724
Building and improvements	3,631,388		3,693,579
Tenant improvements	483,801		442,808
	$	4,793,080	$	4,834,111

Business acquisition, purchase price allocation

	August 5,
	2010
Building and tenant improvements	$	98,188
Intangible assets acquired	28,856
Below market lease liabilities assumed	(683		)
Total	$	126,361

Schedule of Intangibles assets and liabilities acquired

	August 5, 2010		Weighted Average Amortization Period (in years)
Intangible assets:
In-place lease value	$	13,584	3
Tenant relationship value	8,870		5
Above market tenant leases acquired	895		1
Below market ground lease acquired	5,507		82
Total	$	28,856	23
Intangible liabilities:
Below market leases acquired	$	683	1

Operating results of acquired property included in parent company results of operations

	For the period from August 5 to December 31, 2010
Revenue:
Rents	$	6,347
Tenant Reimbursements	933
Other	45
Total revenue	$	7,325
Loss from operations (includes depreciation and intangible asset amortization)	$	(3,602	)

Supplemental pro forma operating data

	December 31,
	2010			2009
	(unaudited)
Pro forma revenues	$	582,642		$	604,440
Pro forma income (loss) from continuing operations	(29,000		)	7,890
Pro forma net income (loss) available to common shareholders	(24,940		)	2,306
Earnings per common share from continuing operations:
Basic — as reported	$	(0.29	)	$	(0.04	)
Basic — as pro forma	$	(0.28	)	$	—
Diluted — as reported	$	(0.29	)	$	(0.04	)
Diluted — as pro forma	$	(0.28	)	$	—
Earnings per common share:
Basic — as reported	$	(0.19	)	$	—
Basic — as pro forma	$	(0.19	)	$	0.02
Diluted — as reported	$	(0.19	)	$	—
Diluted — as pro forma	$	(0.19	)	$	0.02