Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Net Income (Loss) Available to Common Stockholders, Diluted	$ 179,550	$ 148,986
Operating activities:
Net income	197,405	166,841
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Gain (Loss) on Extinguishment of Debt	(977)	0
Asset Impairment Charges	10,195	0
Gain on sale of real estate	(28,462)	(3,885)
Gain on insurance recovery	(606)	(3,837)
Deferred income tax expense (benefit)	911	(664)
Costs associated with loan refinancing or payoff	1,491	905
Equity in income from joint ventures	(86)	(501)
Distributions from joint ventures	442	511
Depreciation and amortization	95,919	79,222
Amortization of deferred financing costs	4,579	3,522
Amortization of above and below market leases, net and tenant improvements	(41)	138
Share-based compensation expense to management and trustees	10,566	8,282
Increase in restricted cash	(744)	(1,463)
Decrease (increase) in mortgage notes accrued interest receivable	875	(188)
Decrease (increase) in accounts receivable, net	10,220	(19,066)
Increase in direct financing lease receivable	(1,003)	(2,503)
Increase in other assets	(2,225)	(5,193)
Decrease in accounts payable and accrued liabilities	(13,969)	(5,260)
Increase (decrease) in unearned rents and interest	15,818	(1,088)
Net cash provided by operating activities	300,308	215,773
Investing activities:
Acquisition of and investments in rental properties and other assets	354,277	177,362
Proceeds from sale of real estate	136,467	20,651
Investment in mortgage notes receivable	(130,076)	(80,786)
Proceeds from mortgage note receivable paydown	16,608	63,876
Investment in promissory notes receivable	1,868	66
Proceeds from promissory note receivable paydown	1,599	0
Proceeds from sale of infrastructure related to issuance of revenue bonds	0	43,462
Proceeds from insurance recovery	579	3,036
Proceeds from Sale of Lease Receivables	0	825
Additions to properties under development	(304,084)	(288,887)
Net cash used by investing activities	(635,052)	(415,251)
Financing activities:
Proceeds from long-term debt facilities	1,175,000	854,360
Principal payments on long-term debt	(667,091)	(587,109)
Deferred financing fees paid	(14,207)	(3,047)
Costs associated with loan refinancing or payoff (cash portion)	(7)	(482)
Net proceeds from issuance of common shares	68,552	142,452
Impact of stock option exercises, net	0	(717)
Purchase of common shares for treasury	(6,729)	(4,211)
Dividends paid to shareholders	(228,861)	(198,678)
Net cash provided by financing activities	326,657	202,568
Effect of exchange rate changes on cash	164	(62)
Net (decrease) increase in cash and cash equivalents	(7,923)	3,028
Cash and cash equivalents at beginning of the year	19,335	4,283
Cash and cash equivalents at end of the year	11,412	7,311
Supplemental schedule of non-cash activity:
Transfer of property under development to rental property	301,612	364,234
Issuance of nonvested shares and restricted share units at fair value, including nonvested shares issued for payment of bonuses	23,893	19,626
Stock Issued During Period, Value, Acquisitions	657,473
Noncash or Part Noncash Acquisition, Net Nonmonetary Assets Acquired (Liabilities Assumed)	12,083	0
Transfer of investment in a direct financing lease to rental properties	35,807	0
Supplemental disclosure of cash flow information:
Cash paid during the year for interest	103,702	83,307
Cash paid during the period for income taxes	1,253	1,380
Interest cost capitalized	7,833	7,983
Decrease in accrued capital expenditures	7,137	5,621
Additional Paid-in Capital [Member]
Supplemental schedule of non-cash activity:
Stock Issued During Period, Value, Acquisitions	$ 657,384	$ 0