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Beneficiaries Equity of the Parent Company (Textual) (Details) - USD ($)		3 Months Ended
	Feb. 21, 2019	Mar. 31, 2019	Mar. 31, 2018	Jan. 03, 2019
Class of Stock [Line Items]
Dividends, Common Stock	$ 33,700,000
Dividends payable, date to be paid	Apr. 18, 2019
Dividends payable, date of record	Apr. 04, 2019
Repurchased and Retired, Shares		1,337,169
Share Price		$ 12.92
Repurchased and Retired, Value		$ 17,281,000
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		982,871	1,479,799