Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash flow from operating activities:
Net income	$ 440,348	$ 187,810
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	154,724	129,296
Impairment charges	21,931	99,952
Equity award expense	12,154	11,216
Gain on sale of operating properties	(58,731)	$ (30,907)
Gain on sale of marketable securities	(32,435)
Gains on change in control of interests	(139,801)	$ (98,286)
Equity in income of joint ventures, net	(119,914)	(69,342)
Equity in income from other real estate investments, net	(19,917)	(10,367)
Distributions from joint ventures and other real estate investments	119,526	125,694
Change in accounts and notes receivable	(5,383)	2,178
Change in accounts payable and accrued expenses	(381)	(1,294)
Change in other operating assets and liabilities	(32,676)	(19,853)
Net cash flow provided by operating activities	339,445	326,097
Cash flow from investing activities:
Acquisition of operating real estate and other related net assets	(586,321)	(362,160)
Improvements to operating real estate	(72,642)	(52,875)
Improvements to real estate under development	(4,362)	(107)
Investment in marketable securities	(257)	(4,556)
Proceeds from sale of marketable securities	59,318	219
Investments and advances to real estate joint ventures	(57,148)	(46,644)
Reimbursements of investments and advances to real estate joint ventures	62,269	113,757
Investment in other real estate investments	(458)	(1,372)
Reimbursements of investments and advances to other real estate investments	22,887	12,907
Collection of mortgage loans receivable	50,729	$ 7,115
Investment in other investments	(190,278)
Proceeds from sale of operating properties	183,332	$ 161,737
Net cash flow used for investing activities	(532,931)	(171,979)
Cash flow from financing activities:
Principal payments on debt, excluding normal amortization of rental property debt	(308,728)	(233,800)
Principal payments on rental property debt	(14,628)	(11,060)
Proceeds under unsecured revolving credit facility, net	125,000	143,060
Proceeds from issuance of unsecured term loan/notes	1,000,000	500,000
Repayments under unsecured term loan/notes	(500,000)	(294,570)
Financing origination costs	(8,903)	(11,911)
Contributions from noncontrolling interests	106,154
Redemption/distribution of noncontrolling interests	(33,348)	(1,059)
Dividends paid	(227,023)	(213,699)
Proceeds from issuance of stock	13,472	12,336
Net cash flow provided by/(used for) financing activities	151,996	(110,703)
Change in cash and cash equivalents	(41,490)	43,415
Cash and cash equivalents, beginning of period	187,322	148,768
Cash and cash equivalents, end of period	145,832	192,183
Interest paid during the period (net of capitalized interest of $2,424 and $737, respectively)	112,582	102,478
Income taxes paid during the period	$ 10,829	$ 10,465