Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash Flows from Operating Activities:
Net Income	$ 148,969	$ 36,396
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	38,095	42,449
Amortization of debt deferred costs and intangibles, net	781	768
Impairment loss	0	14,986
Equity in earnings of real estate joint ventures and partnerships, net	(5,993)	(5,317)
Gain on sale of property	(109,045)	(15,763)
Distributions of income from real estate joint ventures and partnerships	4,115	3,253
Changes in accrued rent, accrued contract receivables and accounts receivable, net	13,821	2,716
Changes in unamortized lease costs and other assets, net	(2,469)	(6,154)
Changes in accounts payable, accrued expenses and other liabilities, net	(26,860)	(21,615)
Other, net	(2,042)	2,215
Net cash provided by operating activities	59,372	53,934
Cash Flows from Investing Activities:
Acquisition of real estate and land	(1,265)	(610)
Development and capital improvements	(29,041)	(51,779)
Proceeds from sale of property and real estate equity investments	255,828	52,794
Real estate joint ventures and partnerships - Investments	(5,987)	(198)
Real estate joint ventures and partnerships - Distribution of capital	1,690	1,896
Purchase of investments	0	(2,491)
Proceeds from investments	250	3,500
Other, net	4,417	607
Net cash provided by investing activities	225,892	3,719
Cash Flows from Financing Activities:
Principal payments of debt	(151,931)	(19,441)
Changes in unsecured credit facilities	0	(14,100)
Proceeds from issuance of common shares of beneficial interest, net	914	877
Repurchase of common shares of beneficial interest, net	(8,108)	0
Common share dividends paid	(50,836)	(49,404)
Debt issuance and extinguishment costs paid	(782)	(153)
Distributions to noncontrolling interests	(884)	(8,651)
Contributions from noncontrolling interests	41	0
Other, net	621	(1,146)
Net cash used in financing activities	(210,965)	(92,018)
Net increase (decrease) in cash, cash equivalents and restricted cash equivalents	74,299	(34,365)
Cash, cash equivalents and restricted cash equivalents at January 1	21,334	41,279
Cash, cash equivalents and restricted cash equivalents at March 31	95,633	6,914
Interest paid during the period (net of amount capitalized of $1,440 and $823, respectively)	$ 21,710	$ 24,138