CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net income	$ 419,222	$ 477,001	$ 454,669
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization (including amounts in discontinued operations)	973,663	828,467	769,881
Amortization of deferred revenue and lease intangibles, net	(24,129)	(18,871)	(15,793)
Other non-cash amortization	5,448	(312)	(16,745)
Stock-based compensation	19,537	20,994	20,653
Straight-lining of rental income, net	(33,792)	(38,687)	(30,540)
Loss on extinguishment of debt, net	14,411	5,564	1,048
Gain on real estate dispositions (including amounts in discontinued operations)	(18,811)	(19,183)	(3,617)
Gain on real estate loan investments	0	(1,455)	(5,056)
Gain on sale of marketable securities	(5,800)	0	(856)
Income tax benefit (including amounts in discontinued operations)	(42,384)	(9,431)	(11,828)
Loss from unconsolidated entities	1,244	139	1,748
Loss (gain) on re-measurement of equity interest upon acquisition, net	176	0	(1,241)
Distributions from unconsolidated entities	23,462	6,508	6,641
Other	6,517	9,416	1,986
Changes in operating assets and liabilities:
Decrease (increase) in other assets	42,316	5,317	(690)
Increase in accrued interest	19,995	7,958	6,806
(Decrease) increase in accounts payable and other liabilities	(9,308)	(18,580)	17,689
Net cash provided by operating activities	1,391,767	1,254,845	1,194,755
Cash flows from investing activities:
Net investment in real estate property	(2,650,788)	(1,468,286)	(1,437,002)
Investment in loans receivable and other	(171,144)	(498,992)	(37,963)
Proceeds from real estate disposals	492,408	118,246	35,591
Proceeds from loans receivable	109,176	73,557	325,518
Purchase of marketable securities	0	(96,689)	0
Proceeds from sale or maturity of marketable securities	76,800	21,689	5,493
Funds held in escrow for future development expenditures	4,003	4,590	19,458
Development project expenditures	(119,674)	(106,988)	(95,741)
Capital expenditures	(107,487)	(87,454)	(81,614)
Investment in unconsolidated operating entity	(26,282)	0	0
Contributions to unconsolidated entities	(30,704)	(5,598)	(2,169)
Other	0	(9,115)	(14,331)
Net cash used in investing activities	(2,423,692)	(2,055,040)	(1,282,760)
Cash flows from financing activities:
Net change in borrowings under credit facilities	(723,457)	540,203	(164,029)
Net cash impact of CCP Spin-Off	(128,749)	0	0
Proceeds from debt	2,512,747	2,007,707	2,767,546
Proceeds from debt related to CCP Spin-Off	1,400,000	0	0
Repayment of debt	(1,435,596)	(1,151,395)	(1,792,492)
Distributions to noncontrolling interest	(3,819)	0	0
Payment of deferred financing costs	(24,665)	(14,220)	(31,277)
Issuance of common stock, net	491,023	242,107	141,343
Cash distribution to common stockholders	(1,003,413)	(875,614)	(802,123)
Cash distribution to redeemable OP unitholders	(15,095)	(5,762)	(5,040)
Purchases of redeemable OP units	(33,188)	(503)	(659)
Contributions from noncontrolling interest	0	491	2,395
Distributions to noncontrolling interest	(12,649)	(9,559)	(9,286)
Other	6,983	24,602	8,618
Net cash provided by financing activities	1,030,122	758,057	114,996
Net (decrease) increase in cash and cash equivalents	(1,803)	(42,138)	26,991
Effect of foreign currency translation on cash and cash equivalents	(522)	2,670	(83)
Cash and cash equivalents at beginning of period	55,348	94,816	67,908
Cash and cash equivalents at end of period	53,023	55,348	94,816
Supplemental disclosure of cash flow information:
Interest paid including swap payments and receipts	391,699	361,144	338,311
Assets and liabilities assumed from acquisitions:
Real estate investments	2,565,960	370,741	223,955
Utilization of funds held for an Internal Revenue Code Section 1031 exchange	(8,911)	0	0
Other assets acquired	20,090	15,280	6,635
Debt assumed	177,857	241,076	183,848
Other liabilities	54,459	24,039	29,868
Deferred income tax liability	52,153	110,728	5,181
Noncontrolling interests	88,085	0	11,693
Equity issued	2,204,585	10,178	0
Non-cash impact of CCP Spin-Off	$ 1,256,404	$ 0	$ 0