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Beneficiaries Equity of the Parent Company (Textual) (Details) - USD ($) $ / shares in Units, $ in Millions		6 Months Ended
	May 23, 2018	Jun. 30, 2018	Jun. 30, 2017
Class of Stock [Line Items]
Dividends, Common Stock		$ 32.5
Dividends payable, date to be paid	Jul. 20, 2018
Dividends payable, date of record	Jul. 06, 2018
Preferred shares authorized		20,000,000	20,000,000
Preferred shares outstanding		0	0
Dividend Declared [Member]
Class of Stock [Line Items]
Dividends Payable, Amount Per Share	$ 0.18
Redeemable Common Limited Partnership Units [Member]
Class of Stock [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share		1,479,799	1,479,799