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Beneficiaries Equity of the Parent Company (Textual) (Details) - USD ($)		3 Months Ended		6 Months Ended
	May 22, 2019	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2019	Jun. 30, 2018	Jan. 03, 2019
Class of Stock [Line Items]
Dividends, Common Stock	$ 33,800,000
Dividends payable, date to be paid	Jul. 19, 2019
Dividends payable, date of record	Jul. 05, 2019
Repurchased and Retired, Shares		0		1,337,169
Share Price				$ 12.92
Repurchased and Retired, Value		$ 0	$ 17,281,000	$ 17,300,000
Maximum [Member]
Class of Stock [Line Items]
Authorized Amount						$ 150,000,000.0
Dividend Declared [Member]
Class of Stock [Line Items]
Dividends Payable, Amount Per Share	$ 0.19
Redeemable Common Limited Partnership Units [Member]
Class of Stock [Line Items]
Redeemable Common Limited Partnership Units Excluded from Computation of Earnings Per Share				981,626	1,479,799