CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 100,356	$ 142,099
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	46,744	45,022
Amortization of financing costs	2,025	2,577
Gain on disposition of properties	(81,965)	(89,063)
Impairment of asset	0	5,000
Stock compensation expense	9,729	5,669
Equity in earnings of unconsolidated affiliates	(3,592)	(12,194)
Gain on disposition of property of unconsolidated affiliates	0	(24,043)
Distributions of operating income from unconsolidated affiliates	4,917	11,747
Other, net	(5,577)	(5,103)
Changes in assets and liabilities
Cash in escrow	1,733	(6,757)
Rents receivable, net	(4,858)	(2,454)
Prepaid expenses and other assets	(11,642)	1,901
Accounts payable and accrued expenses	(1,511)	7,738
Other liabilities	134	3,203
Net cash provided by operating activities	56,493	85,342
CASH FLOWS FROM INVESTING ACTIVITIES
Acquisition of real estate	(292,136)	(292,671)
Deposits for properties under contract	(8,576)	0
Redevelopment and property improvement costs	(94,459)	(159,360)
Deferred leasing costs	(5,451)	(5,931)
Investments in and advances to unconsolidated affiliates	(68,153)	(10,581)
Return of capital from unconsolidated affiliates	50,622	9,574
Proceeds from disposition of property of unconsolidated affiliates	0	38,392
Change in control of previously consolidated investment	(2,578)	0
Proceeds from notes receivable	42,819	15,984
Issuance of notes receivable	(148,203)	(48,350)
Proceeds from sale of properties, net	150,379	198,434
Net cash used in investing activities	(375,736)	(254,509)
CASH FLOWS FROM FINANCING ACTIVITIES
Principal payments on mortgage and other notes	(292,815)	(92,468)
Principal payments on unsecured debt	(516,790)	(174,815)
Proceeds received from mortgage and other notes	70,437	85,859
Proceeds received from unsecured debt	616,315	253,200
Loan proceeds held as restricted cash	8,462	43,315
Deferred financing and other costs	(5,288)	(3,155)
Capital contributions from noncontrolling interests	204,412	34,895
Distributions to noncontrolling interests	(74,612)	(79,575)
Dividends paid to Common Shareholders	(71,674)	(69,788)
Proceeds from issuance of Common Shares, net of issuance costs of $7,317 and $655, respectively	357,262	26,933
Net cash provided by financing activities	295,709	24,401
Decrease in cash and cash equivalents	(23,534)	(144,766)
Cash and cash equivalents, beginning of period	72,776	217,580
Cash and cash equivalents, end of period	49,242	72,814
Supplemental disclosure of cash flow information
Cash paid during the period for interest, net of capitalized interest of $14,936 and $11,847, respectively	28,116	34,146
Cash paid for income taxes	1,267	2,543
Supplemental disclosure of non-cash investing activities
Acquisition of real estate through assumption of debt	60,668	90,765
Acquisition of capital lease obligation	76,461	0
Acquisition of real estate through issuance of OP Units	29,336	0
Acquisition of real estate through conversion of notes receivable	0	6,886
Acquisition of real estate through assumption of restricted cash	0	28,192
Disposition of air rights through issuance of notes receivable	0	(29,793)
Assumption of accounts payable and accrued expenses through acquisition of real estate	1,809	0
Assumption of prepaid expenses and other assets through acquisition of real estate	1,074	0
Change in control of previously consolidated investment
Real estate, net	90,559	0
Investment in unconsolidated affiliates	(21,421)	0
Other assets and liabilities	3,997	0
Noncontrolling interest	(75,713)	0
Change in control of previously consolidated investment	$ (2,578)	$ 0