Investments in Real Estate Partnerships - Schedule of Investments in Real Estate Partnerships (Parenthetical) (Details) - USD ($) $ in Thousands		1 Months Ended		3 Months Ended	12 Months Ended
		Dec. 31, 2019		Sep. 30, 2019	Dec. 31, 2019		Dec. 31, 2018	Dec. 31, 2017	Jan. 31, 2020
Schedule of Equity Method Investments [Line Items]
Provision for impairment, net of tax					$ 54,174		$ 38,437	$ 0
Ownership Percentage		0.00%			0.00%		0.00%
Equity One JV Portfolio, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Provision for impairment, net of tax				$ (10,900)
Ownership Percentage		30.00%	[1]		30.00%	[1]	30.00%
US Regency Retail 1, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	[2]	20.01%			20.01%		20.01%
US Regency Retail 1, LLC [Member] | Accounts Payable and Accrued Liabilities [Member]
Schedule of Equity Method Investments [Line Items]
Negative Investment Balance				$ 3,900
Other Investments in Real Estate Partnerships [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage		35.00%			35.00%		9.38%
Additional Ownership Percentage Acquired		9.00%
Other Investments in Real Estate Partnerships [Member] | Subsequent Event [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage									16.62%

[1] During the third quarter of 2019, a $10.9 million impairment of real estate was recognized within the NYC partnership from changes in the expected hold periods of various properties.

[2] The USAA partnership has distributed proceeds from debt refinancing and real estate sales in excess of Regency’s carrying value of its investment resulting in a negative investment balance of $3.9 million, which is recorded within Accounts Payable and other liabilities in the Consolidated Balance Sheets.