Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
OPERATING ACTIVITIES
Net income	$ 218,424	$ 172,289	$ 167,608
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization, including discontinued operations	174,796	170,814	161,099
Gain on sale of real estate	(28,330)	(4,401)	(28,855)
Early extinguishment of debt	19,072	10,545	13,304
Income from real estate partnerships	1,416	1,243	1,498
Other, net	177	733	2,704
Changes in assets and liabilities, net of effects of acquisitions and dispositions:
Increase in accounts receivable, net	(9,200)	(3,063)	(6,321)
(Increase) decrease in prepaid expenses and other assets	(7,422)	(4,222)	69
(Decrease) increase in accounts payable and accrued expenses	(9,995)	4,253	5,325
Increase in security deposits and other liabilities	3,729	425	1,063
Net cash provided by operating activities	359,835	346,130	314,498
INVESTING ACTIVITIES
Acquisition of real estate	(154,313)	(9,154)	(87,276)
Capital expenditures - development and redevelopment	(236,437)	(314,654)	(243,073)
Capital expenditures - other	(46,096)	(46,304)	(47,069)
Proceeds from sale of real estate	97,422	10,406	42,866
Investment in real estate partnerships	(2,802)	(6,731)	0
Distribution from real estate partnership in excess of earnings	512	565	790
Leasing costs	(22,382)	(35,286)	(12,393)
Repayment of mortgage and other notes receivable, net	10,333	5,008	957
Net cash used in investing activities	(353,763)	(396,150)	(345,198)
FINANCING ACTIVITIES
Net borrowings (repayments) under revolving credit facility, net of costs	53,500	0	(1,929)
Issuance of senior notes, net of costs	456,151	244,579	564,389
Redemption and retirement of senior notes	(219,228)	(134,240)	(293,360)
Issuance of mortgages, capital leases and notes payable, net of costs	0	0	860
Repayment of mortgages, capital leases and notes payable	(181,315)	(94,422)	(173,735)
Issuance of common shares	110,855	216,155	186,548
Dividends paid to common and preferred shareholders	(243,314)	(215,216)	(193,016)
Distributions to and redemptions of noncontrolling interests	(9,626)	(7,812)	(7,118)
Net cash (used in) provided by financing activities	(32,977)	9,044	82,639
(Decrease) Increase in cash and cash equivalents	(26,905)	(40,976)	51,939
Cash and cash equivalents at beginning of year	47,951	88,927	36,988
Cash and cash equivalents at end of year	$ 21,046	$ 47,951	$ 88,927