CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities:
Net income	$ 235,781	$ 237,877
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation expense	140,621	127,216
Amortization of deferred financing costs	1,826	1,936
Amortization of debt premium	(4,621)	(4,779)
Amortization of stock-based compensation	4,319	3,835
Equity in (income) loss of, and return on, unconsolidated real estate entities and noncontrolling interests, net of eliminations	(5,768)	6,438
Casualty and impairment loss (gain), net	11,688	(2,202)
Abandonment of development pursuits	265	0
Cash flow hedge losses reclassified to earnings	1,752	1,374
Gain on sale of real estate assets	(97,012)	(81,055)
(Increase) decrease in cash in operating escrows	(6,433)	3,009
Increase in resident security deposits, prepaid expenses and other assets	(10,630)	(8,559)
Increase (decrease) in accrued expenses, other liabilities and accrued interest payable	21,674	(7,308)
Net cash provided by operating activities	293,462	277,782
Cash flows from investing activities:
Development/redevelopment of real estate assets including land acquisitions and deferred development costs	(259,573)	(266,588)
Acquisition of real estate assets, including partnership interest	0	(170,022)
Capital expenditures - existing real estate assets	(8,015)	(11,618)
Capital expenditures - non-real estate assets	(2,429)	(3,264)
Proceeds from sale of real estate, net of selling costs	159,985	68,709
Increase in cash in deposit escrows	(126,467)	(69,227)
Insurance proceeds for property damage claims	4,095	8,702
Mortgage note receivable lending	(4,795)	0
(Decrease) increase in payables for construction	(4,326)	842
Distributions from unconsolidated real estate entities	11,952	58,652
Investments in unconsolidated real estate entities	(5,774)	(913)
Net cash used in investing activities	(235,347)	(384,727)
Cash flows from financing activities:
Issuance of common stock, net	56,817	1,102
Dividends paid	(185,192)	(171,151)
Repayments of mortgage notes payable, including prepayment penalties	(21,037)	(19,682)
Payment of deferred financing costs	(2,315)	(6,176)
Distributions to DownREIT partnership unitholders	(11)	(10)
Contributions from joint venture and profit-sharing partners	1,038	0
Distributions to joint venture and profit-sharing partners	(104)	(104)
Preferred interest obligation redemption and dividends	(600)	0
Net cash used in financing activities	(151,404)	(196,021)
Net decrease in cash and cash equivalents	(93,289)	(302,966)
Cash and cash equivalents, beginning of period	214,994	400,507
Cash and cash equivalents, end of period	121,705	97,541
Cash paid during the period for interest, net of amount capitalized	$ 34,503	$ 46,011