Statement of Cash Flows (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash Flow - Operating Activities
Net Income	$ 70,446,000	$ 45,787,000	$ 2,180,000
Adjustments to net income
Depreciation and amortization, including intangible assets and deferred financing costs	46,720,000	14,972,000	5,088,000
Loss from equity investments in real estate in excess of distributions received	1,868,000	0	326,000
Issuance of shares to affiliate in satisfaction of fees due	11,184,000	4,562,000	2,676,000
Gain on sale of real estate	(787,000)	0	0
Unrealized loss on foreign currency transactions and others	3,000	85,000	13,000
Realized (gain) loss on foreign currency transactions and other	(6,055,000)	(777,000)	2,519,000
Straight-line rent adjustment and amortization of rent-related intangibles	(11,616,000)	(4,040,000)	(3,425,000)
Settlement Of Derivative Liability	(5,131,000)	0	0
Amortization on discount on commercial mortgage-backed securities			(668,000)
Impairment charges on net investments in properties and CMBS	(70,000)		23,904,000
Increase in accounts receivable and prepaid expenses	(2,949,000)	(2,430,000)	(514,000)
Increase in accounts payable and accrued expenses	3,621,000	5,075,000	749,000
Increase in prepaid and deferred rental income	1,485,000	3,868,000	2,432,000
(Decrease) increase in due to affiliates	(2,197,000)	3,574,000	78,000
Net changes in other operating assets and liabilities	(5,007,000)	(1,158,000)	(10,000)
Net Cash Provided By Operating Activities	101,515,000	69,518,000	35,348,000
Cash Flows - Investing Activities
Distributions received from equity investments in real estate in excess of equity income	90,571,000	2,761,000	2,282,000
Acquisitions of real estate and direct financing leases and other capital expenditures (a)	(658,546,000)	(917,897,000)	(430,448,000)
Capital contributions to equity investments in real estate (a)	(228,519,000)	(10,648,000)	(22,798,000)
VAT paid in connection with acquisition of real estate	(4,592,000)	(53,241,000)	(14,881,000)
VAT refunded in connection with acquisitions in real estate	29,336,000	40,441,000	0
Proceeds from sale of real estate	19,821,000	1,690,000	0
Funds placed in escrow	(196,291,000)	(103,045,000)	(111,335,000)
Funds released from escrow	186,958,000	98,502,000	107,690,000
Payment of deferred acquisition fees to affiliate	(14,455,000)	(7,204,000)	(3,263,000)
Proceeds from repayment of notes receivable	49,560,000	7,440,000	0
Investment in securities	(2,394,000)	0	0
Purchase of notes receivable	(30,000,000)	(90,695,000)	(7,000,000)
Net Cash Used In Investing Activities	(758,551,000)	(1,031,896,000)	(479,753,000)
Cash Flows - Financing Activities
Distributions paid	(102,503,000)	(60,937,000)	(27,193,000)
Contributions from noncontrolling interests	1,197,000	412,000	103,364,000
Distributions to noncontrolling interests	(23,214,000)	(12,959,000)	(71,946,000)
Scheduled payments of mortgage principal	(14,136,000)	(6,541,000)	(4,494,000)
Prepayments of mortgage principal	0	(53,017,000)	0
Proceeds from mortgage financing (b)	243,517,000	425,881,000	170,805,000
Funds placed in escrow	17,919,000	7,168,000	0
Funds released from escrow	(8,932,000)	(3,593,000)	0
Proceeds from loan from an affiliate	90,000,000	0	0
Repayment of loan from an affiliate	(90,000,000)	0	0
Payment of financing costs and mortgage deposits, net of deposits refunded	(9,423,000)	(4,094,000)	(4,574,000)
Proceeds from issuance of shares, net of issuance costs	575,251,000	557,895,000	404,200,000
Purchase of treasury stock	(9,060,000)	(5,730,000)	(2,314,000)
Net Cash Provided By Financing Activities	670,616,000	844,485,000	567,848,000
Change in Cash and Cash Equivalents During the Year
Effect of exchange rate on cash	4,401,000	(916,000)	(3,458,000)
Net increase (decrease) in cash and cash equivalents	17,981,000	(118,809,000)	119,985,000
Cash and cash equivalents, beginning of year	162,745,000	281,554,000	161,569,000
Cash and cash equivalents, end of year	180,726,000	162,745,000	281,554,000
Supplemental Cash Flow Information [Abstract]
Deferred Acquisition Fees Payable	$ 17,400,000	$ (19,100,000)	$ (7,600,000)