CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net income	$ 791,525	$ 586,381
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation expense	391,414	355,664
Amortization of deferred financing costs	5,664	5,117
Amortization of debt premium	(14,146)	(19,571)
(Gain) loss on extinguishment of debt, net	2,461	(26,736)
Amortization of stock-based compensation	12,103	11,980
Equity in loss of, and return on, unconsolidated entities and noncontrolling interests, net of eliminations	11,756	13,502
Casualty and impairment (gain) loss, net	(3,935)	(17,303)
Abandonment of development pursuits	1,598	0
Cash flow hedge losses reclassified to earnings	4,682	4,334
Gain on sale of real estate assets	(348,675)	(146,745)
Increase in cash in operating escrows	(4,563)	(8,409)
(Increase) decrease in resident security deposits, prepaid expenses and other assets	(16,127)	2,986
Increase in accrued expenses, other liabilities and accrued interest payable	17,911	33,072
Net cash provided by operating activities	851,668	794,272
Cash flows from investing activities:
Development/redevelopment of real estate assets including land acquisitions and deferred development costs	(869,342)	(1,265,829)
Acquisition of real estate assets, including partnership interest	(393,916)	0
Capital expenditures - existing real estate assets	(43,020)	(40,358)
Capital expenditures - non-real estate assets	(5,513)	(4,887)
Proceeds from sale of real estate, net of selling costs	404,731	232,415
Increase in cash in deposit escrows	(59,263)	0
Insurance proceeds for property damage claims	17,196	44,142
Mortgage note receivable lending	(11,074)	0
Increase in payables for construction	1,311	1,010
Distributions from unconsolidated real estate entities	94,748	47,873
Investments in unconsolidated real estate entities	(2,449)	(881)
Net cash used in investing activities	(866,591)	(986,515)
Cash flows from financing activities:
Issuance of common stock, net	14,147	674,631
Dividends paid	(541,485)	(484,251)
Net borrowings under unsecured credit facility	170,000	0
Repayments of mortgage notes payable, including prepayment penalties	(161,095)	(743,653)
Issuance of unsecured notes	474,838	574,066
Repayment of unsecured notes	(250,000)	0
Payment of deferred financing costs	(10,910)	(4,741)
Payment for termination of forward interest rate swaps	(14,847)	0
Distributions to DownREIT partnership unitholders	(30)	(28)
Distributions to joint venture and profit-sharing partners	(303)	(274)
Redemption of preferred interest obligation	0	(14,410)
Net cash (used in) provided by financing activities	(319,685)	1,340
Net decrease in cash and cash equivalents	(334,608)	(190,903)
Cash and cash equivalents, beginning of period	400,507	509,460
Cash and cash equivalents, end of period	65,899	318,557
Cash paid during the period for interest, net of amount capitalized	$ 137,720	$ 149,097