Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
OPERATING ACTIVITIES
Net income	$ 2,871	$ 13,596
Results from discontinued operations		(331)
Income from continuing operations	2,871	13,265
Adjustments to reconcile income from continuing operations to net cash provided by operating activities:
Deferred rent revenue and amortization of lease intangibles	(1,428)	223
Depreciation and amortization	15,253	12,155
Amortization of debt issuance costs and debt fair value adjustments	974	865
Early extinguishment of debt		25,867
Loan transfer and consent fees		9,019
Gain on acquisition of controlling interests		(46,371)
Stock-based compensation expense	699	491
Other, net	416	935
Changes in operating assets and liabilities
Change in restricted cash	(824)	1,391
Change in accounts receivable	1,493	(1,409)
Change in other assets	(1,309)	(1,456)
Change in accounts payable and accrued expenses	584	(524)
Change in security deposits and other liabilities	(229)	131
Net cash provided by operating activities of continuing operations	18,500	14,582
Net cash provided by operating activities of discontinued operations		688
Net cash provided by operating activities	18,500	15,270
INVESTING ACTIVITIES
Acquisition of real estate, net of cash acquired	(32,918)	(128,877)
Capital expenditures	(6,001)	(962)
Change in restricted cash	(139)	(1,403)
Cash acquired from acquisition of controlling interests in real estate joint ventures		15,222
Leasing commissions	(467)	(206)
Purchase of marketable securities		(33,103)
Maturity of marketable securities	1,613
Net cash used in investing activities of continuing operations	(37,912)	(149,329)
Net cash used in investing activities of discontinued operations		(220)
Net cash used in investing activities	(37,912)	(149,549)
FINANCING ACTIVITIES
Issuance of secured notes payable	21,900
Repayment of secured notes payable	(1,161)	(260,916)
Defeasance costs on repayment of secured notes payable		(24,345)
Loan transfer and consent fees paid		(8,350)
Repayment of unsecured notes payable		(38,013)
Repayment of notes payable to affiliates		(19,279)
Debt issuance costs	(924)	(2,507)
Proceeds from issuance of common stock, net		596,541
Proceeds from private placement of common units		5,410
Dividends paid to common stock and unitholders	(12,113)	(9,784)
Deferred offering costs	(361)
Payments to nonaccredited investors		(6,075)
Distributions to Predecessor's controlling and noncontrolling interests		(39,960)
Net cash provided by financing activities	7,341	192,722
Net (decrease) increase in cash and cash equivalents	(12,071)	58,443
Cash and cash equivalents, beginning of period	112,723	41,953
Cash and cash equivalents, end of period	$ 100,652	$ 100,396