Consolidated Statements of Cash Flows (USD $)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Operating activities
Net income	$ 138,280,000		$ 294,840,000		$ 212,716,000
Adjustments to reconcile net income to net cash provided from (used in) operating activities:
Depreciation and amortization expenses	873,960,000		533,585,000		423,605,000
Other amortization expenses	8,097,000		15,185,000		16,851,000
Provision for loan losses	2,110,000	[1]	27,008,000	[2]	2,010,000	[3]
Impairment of assets	0		29,287,000		12,194,000
Stock-based compensation expense	20,177,000		18,521,000		10,786,000
Loss on derivatives	4,470,000		(1,825,000)		0
Loss (gain) on extinguishment of debt, net	(909,000)		(775,000)		(979,000)
Income (loss) from unconsolidated entities	(8,187,000)		2,482,000		5,772,000
Rental income less than (in excess of) cash received	(46,068,000)		(32,362,000)		(31,578,000)
Amortization related to above (below) market leases, net	460,000		165,000		(2,507,000)
Gain (loss) on sales of properties, net	(49,138,000)		(100,549,000)		(61,160,000)
Distributions by unconsolidated entities operating	(8,885,000)		(17,607,000)		(6,149,000)
Increase (decrease) in accrued expenses and other liabilities	67,557,000		38,213,000		10,653,000
Decrease (increase) in receivables and other assets	(47,571,000)		(18,285,000)		(4,744,000)
Net cash provided from (used in) operating activities	988,497,000		818,133,000		588,224,000
Investing activities
Cash disbursed for acquisitions	(3,597,955,000)		(2,923,251,000)		(4,514,271,000)
Cash disbursed for capital improvements to existing properties	(135,832,000)		(135,450,000)		(89,247,000)
Cash disbursed for construction in progress	(247,560,000)		(286,410,000)		(301,604,000)
Capitalized interest	(6,700,000)		(9,777,000)		(13,164,000)
Investment in real estate loans receivable	(117,059,000)		(665,094,000)		(51,477,000)
Other investments, net of payments	(15,634,000)		25,425,000		(22,986,000)
Principal collected on real estate loans receivable	102,886,000		35,020,000		188,811,000
Contributions to unconsolidated entities	(99,769,000)		(227,735,000)		(2,784,000)
Distributions by unconsolidated entities investing	30,853,000		13,136,000		9,135,000
Proceeds from (payments on) derivatives investing	(6,803,000)		6,652,000		0
Decrease (increase) in restricted cash	79,957,000		(35,766,000)		30,248,000
Proceeds from sales of real property	482,023,000		610,271,000		247,210,000
Net cash provided from (used in) investing activities	(3,531,593,000)		(3,592,979,000)		(4,520,129,000)
Financing activities
Net increase (decrease) under unsecured lines of credit arrangements	130,000,000		(610,000,000)		310,000,000
Proceeds from issuance of senior unsecured notes	1,756,192,000		2,025,708,000		1,381,086,000
Payments to extinguish senior unsecured notes	(517,625,000)		(370,524,000)		(3,000)
Secured debt issued	89,208,000		157,418,000		119,030,000
Payments on secured debt	(674,103,000)		(406,210,000)		(83,998,000)
Net proceeds from the issuance of common stock	1,854,637,000		3,581,292,000		2,137,594,000
Net proceeds from issuance of preferred stock	0		277,687,000		696,437,000
Redemption of preferred stock	0		(275,000,000)		0
Decrease (increase) in deferred loan expenses	(13,503,000)		(7,152,000)		(28,867,000)
Contributions by noncontrolling interests	5,072,000	[4]	24,115,000	[4]	8,604,000	[4]
Distributions to noncontrolling interests	(35,592,000)	[4]	(29,353,000)	[4]	(30,705,000)	[4]
Acquisitions of non controlling interests	(23,247,000)		0		0
Cash distributions to stockholders	(906,275,000)		(722,450,000)		(544,248,000)
Other financing activities	2,906,000		(403,000)		(1,113,000)
Net cash provided from (used in) financing activities	1,667,670,000		3,645,128,000		3,963,817,000
Effect of foreign currency translation on cash and cash equivalents	442,000		0		0
Increase (decrease) in cash and cash equivalents	(874,984,000)		870,282,000		31,912,000
Cash and cash equivalents at beginning of period	1,033,764,000		163,482,000		131,570,000
Cash and cash equivalents at end of period	158,780,000		1,033,764,000		163,482,000
Supplemental cash flow information:
Interest paid	447,108,000		369,511,000		285,884,000
Income taxes paid	$ 12,110,000		$ 3,071,189.98		$ 389,000

[1] Provision and charge-off amounts relate to one active adult community in our seniors housing triple-net segment.

[2] Provision and charge-off amounts relate to one entrance fee community in our seniors housing triple-net segment.

[3] Provision and charge-off amounts relate to one hospital in our medical facilities segment.

[4] Includes amounts attributable to redeemable noncontrolling interests. See accompanying notes.