Consolidated Statements of Cash Flows (Unaudited) (USD $)	9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012
Operating activities
Net income	$ 112,588,000		$ 187,836,000
Adjustments to reconcile net income to net cash provided from (used in) operating activities:
Depreciation and amortization	630,579,000		393,243,000
Other amortization expenses	6,662,000		11,702,000
Provision for loan losses	0		27,008,000
Impairment of assets	0		(6,952,000)
Stock-based compensation expense	16,650,000		16,229,000
Loss (gain) on derivatives, net	4,465,000		(1,712,000)
Loss (gain) on extinguishment of debt, net	(4,376,000)		791,000
Income from unconsolidated entities	3,529,000		(2,250,000)
Rental income in excess of cash received	(31,226,000)		(32,069,000)
Amortization related to above (below) market leases, net	313,000		767,000
Loss (gain) on sales of properties, net	(57,202,000)		(46,046,000)
Distributions by unconsolidated entities	0		3,920,000
Increase (decrease) in accrued expenses and other liabilities	9,646,000		16,417,000
Decrease (increase) in receivables and other assets	(65,721,000)		(19,318,000)
Net cash provided from (used in) operating activities	625,907,000		563,470,000
Investing activities
Investment in real property, net of cash acquired	(3,354,716,000)		(2,119,796,000)
Capitalized interest	(4,698,000)		(7,113,000)
Investment in real estate loans receivable	(77,336,000)		(35,894,000)
Other investments, net of payments	(16,589,000)		26,752,000
Principal collected on real estate loans receivable	85,555,000		16,577,000
Contributions to unconsolidated entities	(381,667,000)		(227,735,000)
Distributions by unconsolidated entities	31,699,000		12,592,000
Proceeds from (payments on) derivatives	60,909,000		4,435,000
Decrease (increase) in restricted cash	68,796,000		(69,809,000)
Proceeds from sales of real property	385,493,000		302,377,000
Net cash provided from (used in) investing activities	(3,202,554,000)		(2,097,614,000)
Financing activities
Net increase (decrease) under unsecured lines of credit arrangements	834,050,000		(610,000,000)
Proceeds from issuance of senior unsecured notes	497,862,000		842,323,000
Payments to extinguish senior unsecured notes	(217,615,000)		(370,524,000)
Secured debt issued	85,140,000		145,713,000
Payments on secured debt	(575,373,000)		(272,399,000)
Net proceeds from the issuance of common stock	1,792,552,000		3,536,232,000
Net proceeds from the issuance of preferred stock	0		277,687,000
Redemption of preferred stock	0		(275,000,000)
Decrease (increase) in deferred loan expenses	(12,398,000)		(5,119,000)
Contributions by noncontrolling interests	5,350,000	[1]	12,106,000	[1]
Distributions to noncontrolling interests	(22,502,000)	[1]	(15,283,000)	[1]
Acquisitions of noncontrolling interests	(23,247,000)		0
Cash distributions to stockholders	(668,797,000)		(513,463,000)
Other financing activities	(1,710,000)		641,000
Net cash provided from (used in) financing activities	1,693,312,000		2,752,914,000
Effect of foreign currency translation on cash and cash equivalents	14,409,000		0
Increase (decrease) in cash and cash equivalents	(868,926,000)		1,218,770,000
Cash and cash equivalents at beginning of period	1,033,764,000		163,482,000
Cash and cash equivalents at end of period	164,838,000		1,382,252,000
Supplemental cash flow information:
Interest paid	342,739,000		275,246,000
Income taxes paid	$ 5,146,096		$ 3,012,000

[1] (1) Includes amounts attributable to redeemable noncontrolling interests.