Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash flow from operating activities:
Net income	$ 303,518	$ 410,516
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	209,440	236,114
Impairment charges	41,235	33,855
Early extinguishment of debt charges	0	12,762
Equity award expense	15,025	14,455
Gain on sale of properties/change in control of interests	(47,382)	(180,461)
Distributions from joint ventures and other real estate investments	78,940	80,900
Change in accounts and notes receivable	(6,908)	6,317
Change in accounts payable and accrued expenses	29,515	26,072
Change in other operating assets and liabilities	(59,206)	(47,075)
Net cash flow provided by operating activities	482,459	516,331
Cash flow from investing activities:
Acquisition of operating real estate and other related net assets	0	(5,407)
Improvements to operating real estate	(228,029)	(193,445)
Acquisition of real estate under development	0	(4,592)
Improvements to real estate under development	(85,609)	(175,129)
Investments in marketable securities	(244)	(63)
Proceeds from sale/repayments of marketable securities	1,920	677
Investments in and advances to real estate joint ventures	(22,129)	(25,781)
Reimbursements of investments in and advances to real estate joint ventures	10,274	7,358
Investments in and advances to other real estate investments	(12,503)	(353)
Reimbursements of investments in and advances to other real estate investments	5,960	10,464
Investment in other financing receivable	(48)	(65)
Collection of mortgage loans receivable	5,402	7,446
Investment in other investments	(2,500)	(357)
Proceeds from sale of operating properties	163,199	596,502
Proceeds from insurance casualty claims	3,000	13,500
Net cash flow (used for)/provided by investing activities	(161,307)	230,755
Cash flow from financing activities:
Principal payments on debt, excluding normal amortization of rental property debt	(6,198)	(202,725)
Principal payments on rental property debt	(9,265)	(10,025)
Proceeds from construction loan financing	8,752	30,366
Proceeds under the unsecured revolving credit facility, net	100,000	122,254
Proceeds from issuance of unsecured notes	350,000
Repayments under unsecured notes	0	(315,095)
Financing origination costs	(7,448)	(1,208)
Payment of early extinguishment of debt charges	(1,531)	(13,308)
Contributions from noncontrolling interests	0	109
Redemption/distribution of noncontrolling interests	(6,489)	(6,046)
Dividends paid	(401,280)	(397,232)
Proceeds from issuance of stock, net	3,351	33,601
Redemption of preferred stock	(350,000)	0
Repurchase of common stock	0	(75,126)
Change in other financing liabilities	(3,315)	(4,778)
Net cash flow used for financing activities	(323,423)	(839,213)
Net change in cash and cash equivalents	(2,271)	(92,127)
Cash and cash equivalents, beginning of the period	143,581	238,513
Cash and cash equivalents, end of the period	141,310	146,386
Interest paid during the period including payment of early extinguishment of debt charges of $1,531 and $13,308, respectively (net of capitalized interest of $10,874 and $13,319 respectively)	111,224	141,371
Joint Ventures [Member]
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in income	(58,960)	(52,486)
Other Real Estate Investments [Member]
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in income	$ (22,758)	$ (24,638)