Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Cash flows from operating activities:
Net income	$ 26,962	$ 17,305
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	11,985	11,671
Gain from disposal of properties classified as discontinued operations	(13,508)
Equity in (earnings) loss of unconsolidated joint venture	(174)	(18)
Distributions from unconsolidated joint venture	191	150
Lease termination fee related to restricted cash		10,865
Stock-based compensation expense	2	29
Changes in operating assets and liabilities, net of liabilities assumed:
Deferred rent	226	375
Other assets	4,284	(1,214)
Interest payable	(63)	(45)
Security deposits	16	(220)
Prepaid rent and deferred revenue	(311)	(2,124)
Accounts payable and accrued expenses	(3,275)	2,253
Net cash provided by operating activities	26,335	39,027
Cash flows from investing activities:
Improvements to real estate assets		(1,539)
Decrease in restricted cash		6,803
Net proceeds from sale of real estate	35,489
Purchase of real estate	(11,479)
Proceeds received from note receivable	1,743
Net cash provided by investing activities	25,753	5,264
Cash flows from financing activities:
Principal payments on mortgage notes payable	(7,616)	(7,204)
Principal payments on mortgage note payable (related parties)	(308)	(285)
Proceeds from note payable (related parties)	26,337
Payments on note payable (related parties)	(26,337)
Payments on note payable		(10,776)
Net repayments on revolving line of credit	(3,305)
Distributions paid to noncontrolling interests	(29,822)	(23,785)
Dividends paid to common stockholders	(7,923)	(6,229)
Net cash used in financing activities	(48,974)	(48,279)
Net increase (decrease) in cash and cash equivalents	3,114	(3,988)
Cash and cash equivalents, beginning of period		3,988
Cash and cash equivalents, end of period	3,114
Supplemental information:
Cash paid for interest	9,869	10,677
Supplemental schedule of non-cash investing and financing activities:
Debt incurred in connection with property acquisitions	11,479
Note receivable received from sale of real estate	18,780
Issuance of common stock upon conversion of O.P. units	$ 821	$ 3,266