Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Operating activities:
Net (loss) income	$ (25,847)	$ 131,943
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Asset Impairment Charges	51,264	0
Equity Method Investment, Other than Temporary Impairment	3,247	0
Gain on sale of real estate	(242)	(16,102)
Deferred income tax benefit	(2,789)	(2,284)
Costs associated with loan refinancing or payoff	820	0
Equity in loss (income) from joint ventures	(2,144)	959
Proceeds from Equity Method Investment, Distribution	0	112
Financing Receivable, Credit Loss, Expense (Reversal)	4,676	0
depreciation and amort cont and discops	86,260	82,098
Amortization of deferred financing costs	3,285	3,019
Amortization of above/below market leases and tenant allowances, net	(260)	(117)
Share-based compensation expense to management and trustees	6,972	6,563
Increase (Decrease) in Operating Lease Assets and Liabilities, Net	560	(290)
Mortgage notes accrued interest receivable	(3,125)	(1,544)
Accounts receivable	(48,014)	12,435
Increase in direct financing lease receivable	0	(117)
Other assets	(5,273)	(5,434)
Accounts payable and accrued liabilities	(20,072)	50
Increase (Decrease) in Deferred Revenue	3,807	383
Net cash provided by operating activities	57,413	209,756
Investing activities:
Acquisition of and investments in real estate and other assets	28,585	418,114
Proceeds from Sale of Real Estate	3,839	95,958
Investment in unconsolidated joint ventures	0	325
Investment in mortgage notes receivable	(3,667)	(33,074)
Proceeds from Sale and Collection of Mortgage Notes Receivable	94	1,954
Investment in promissory notes receivable	0	9,068
Proceeds from promissory note receivable paydown	69	3,574
Additions to properties under development	(24,728)	(102,101)
Net cash used by investing activities	(52,978)	(461,196)
Financing activities:
Proceeds from long-term debt facilities	750,000	422,000
Principal payments on long-term debt	0	(218,150)
Deferred financing fees paid	(2,859)	(276)
Proceeds from (Payments for) Other Financing Activities	(820)	0
Net proceeds from issuance of common shares	713	231,407
Payment, Tax Withholding, Share-based Payment Arrangement	0	(732)
Purchase of common shares for treasury	(6,769)	(9,499)
payments for repurchase of common stock, repurchase program	(105,994)	0
Dividends paid to shareholders	(160,392)	(179,989)
Net cash provided by financing activities	473,879	244,761
Effect of exchange rate changes on cash	(158)	109
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	478,156	(6,570)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	1,009,596	11,937
Cash and Cash Equivalents, at Carrying Value	1,006,981	6,927
Restricted Cash and Cash Equivalents	2,615	5,010
Supplemental schedule of non-cash activity:
Transfer of property under development to rental property	20,089	282,275
Issuance of nonvested shares and restricted share units at fair value, including nonvested shares issued for payment of bonuses	19,956	17,590
Financing Receivable, Allowance for Credit Loss	6,839	0
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	0	227,355
Operating Lease, Cost	0	251,934
Straight-Line Rent Receivable	65,704
Other Real Estate, Additions	0	14,000
Noncash or Part Noncash Acquisition, Debt Assumed	0	18,585
Supplemental disclosure of cash flow information:
Interest Paid, Excluding Capitalized Interest, Operating Activities	72,096	70,954
Cash paid during the period for income taxes	497	1,066
Interest cost capitalized	504	4,667
Change in accrued capital expenditures	$ (9,576)	$ 8,854