Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Net income	$ 337,830	$ 284,907
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	155,924	144,139
Amortization of deferred financing costs	9,230	9,246
Non-cash interest expense related to amortization of discount on equity component of exchangeable senior notes	3,525	3,827
Compensation expense related to stock-based awards	8,455	7,244
(Gain) loss on real estate transactions and impairment of real estate	(30,807)	6,019
Distributions from unconsolidated real estate ventures in excess of earnings	5,235	3,498
Changes in operating assets and liabilities:
Other assets	(639)	(15,303)
Accounts payable and accrued expenses	27,677	6,425
Other liabilities	12,597	(373)
Net cash provided by operating activities	529,027	449,629
Cash flows from investing activities:
Acquisition of real estate assets	(327,011)	(119,040)
Development and redevelopment of real estate assets	(45,376)	(20,670)
Proceeds from sale of real estate assets, investments in real estate ventures and other assets	51,889	18,565
Investment in unconsolidated real estate ventures	(52,806)	(3,021)
Return of investment in unconsolidated real estate ventures	47,964	581
Issuance of notes receivable	(13,889)	0
Principal payments received from notes receivable	25,226	44,869
Purchase of equipment and fixtures	(3,026)	(5,635)
Net cash used in investing activities	(317,029)	(84,351)
Cash flows from financing activities:
Proceeds from the sale of common stock, net of offering costs	33,780	0
Proceeds from notes payable and revolving lines of credit	973,386	1,023,170
Principal payments on notes payable and revolving lines of credit	(787,939)	(1,020,144)
Principal payments on notes payable to trusts	(21,650)	0
Deferred financing costs	(7,055)	(5,172)
Repurchase of exchangeable senior notes	(80,270)	(19,726)
Net proceeds from exercise of stock options	1,170	1,266
Redemption of Operating Partnership units held by noncontrolling interests	(2,558)	(2,510)
Contributions from noncontrolling interests	122	0
Dividends paid on common stock	(315,608)	(294,754)
Distributions to noncontrolling interests	(24,837)	(24,141)
Net cash used in financing activities	(231,459)	(342,011)
Net increase (decrease) in cash, cash equivalents, and restricted cash	(19,461)	23,267
Cash, cash equivalents, and restricted cash, beginning of the period	86,044	57,742
Cash, cash equivalents, and restricted cash end of the period	66,583	81,009
Supplemental schedule of cash flow information
Interest paid	117,627	107,144
Income taxes paid	803	8,086
Supplemental schedule of noncash investing and financing activities:
Noncontrolling interests in Operating Partnership	(955)	0
Common stock and paid-in capital	955	0
Acquisitions of real estate assets
Real estate assets, net	382,765	92,163
Notes payable assumed	(87,500)	(9,463)
Accrued construction costs and capital expenditures
Acquisition of real estate assets	275	4,874
Development and redevelopment of real estate assets	0	1,558
Accounts payable and accrued expenses	(275)	(6,432)
Acquisitions of real estate assets
Acquisitions of real estate assets
Real estate assets, net	88,842	20,100
Value of Operating Partnership units issued	(1,877)	(8,810)
Notes payable assumed	(87,500)	(9,463)
Investment in unconsolidated real estate ventures	535	0
Other noncontrolling interests	$ 0	$ (1,827)