Investments in Real Estate Partnerships - Schedule of Investments in Real Estate Partnerships (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) property		Dec. 31, 2019 USD ($) property		Dec. 31, 2018 USD ($)	Jan. 31, 2020
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%		0.00%
Real Estate Partnerships, Number of Properties | property	114		116
Investments in real estate partnerships	$ 467,155		$ 469,522
Total assets of the Partnership	10,936,904		11,132,253
Income (Loss) from Equity Method Investments	34,169		60,956		$ 42,974
Net income	47,317		243,258		$ 252,325
Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total assets of the Partnership	3,067,227		3,158,884
Net Income [Member]
Schedule of Equity Method Investments [Line Items]
Net income	$ 91,421		$ 171,204
GRI - Regency, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	40.00%		40.00%
Real Estate Partnerships, Number of Properties | property	67		68
Investments in real estate partnerships	$ 179,728		$ 187,597
Income (Loss) from Equity Method Investments	25,425		43,536
GRI - Regency, LLC [Member] | Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total assets of the Partnership	1,583,097		1,612,459
GRI - Regency, LLC [Member] | Net Income [Member]
Schedule of Equity Method Investments [Line Items]
Net income	$ 56,244		$ 96,721
Equity One JV Portfolio, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	30.00%	[1]	30.00%	[2]
Real Estate Partnerships, Number of Properties | property	4	[1]	6	[2]
Investments in real estate partnerships	$ 27,627	[1]	$ 41,422	[2]
Income (Loss) from Equity Method Investments	488	[1]	(9,967)	[2]
Equity One JV Portfolio, LLC [Member] | Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total assets of the Partnership	205,332	[1]	260,512	[2]
Equity One JV Portfolio, LLC [Member] | Net Income [Member]
Schedule of Equity Method Investments [Line Items]
Net income	$ 4,241	[1]	$ (5,832)	[2]
Columbia Regency Retail Partners, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	20.00%		20.00%
Real Estate Partnerships, Number of Properties | property	7		7
Investments in real estate partnerships	$ 8,699		$ 9,201
Income (Loss) from Equity Method Investments	1,030		1,626
Columbia Regency Retail Partners, LLC [Member] | Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total assets of the Partnership	136,120		139,253
Columbia Regency Retail Partners, LLC [Member] | Net Income [Member]
Schedule of Equity Method Investments [Line Items]
Net income	$ 5,383		$ 8,406
Columbia Regency Retail Partners, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	20.00%		20.00%
Real Estate Partnerships, Number of Properties | property	13		13
Investments in real estate partnerships	$ 37,882		$ 39,453
Income (Loss) from Equity Method Investments	1,045		1,748
Columbia Regency Retail Partners, LLC [Member] | Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total assets of the Partnership	377,246		385,960
Columbia Regency Retail Partners, LLC [Member] | Net Income [Member]
Schedule of Equity Method Investments [Line Items]
Net income	$ 5,103		$ 8,742
Cameron Village, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	30.00%		30.00%
Real Estate Partnerships, Number of Properties | property	1		1
Investments in real estate partnerships	$ 10,108		$ 10,641
Income (Loss) from Equity Method Investments	757		1,062
Cameron Village, LLC [Member] | Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total assets of the Partnership	94,551		96,101
Cameron Village, LLC [Member] | Net Income [Member]
Schedule of Equity Method Investments [Line Items]
Net income	$ 2,531		$ 3,572
RegCal, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	25.00%		25.00%
Real Estate Partnerships, Number of Properties | property	6		6
Investments in real estate partnerships	$ 25,908		$ 26,417
Income (Loss) from Equity Method Investments	1,296		3,796
RegCal, LLC [Member] | Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total assets of the Partnership	107,283		109,226
RegCal, LLC [Member] | Net Income [Member]
Schedule of Equity Method Investments [Line Items]
Net income	$ 5,397		$ 16,276
US Regency Retail 1, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	20.01%	[3]	20.01%	[4]
Real Estate Partnerships, Number of Properties | property	7	[3]	7	[4]
Investments in real estate partnerships	$ 0	[3]	$ 0	[4]
Income (Loss) from Equity Method Investments	790	[3]	1,028	[4]
US Regency Retail 1, LLC [Member] | Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total assets of the Partnership	85,006	[3]	87,231	[4]
US Regency Retail 1, LLC [Member] | Net Income [Member]
Schedule of Equity Method Investments [Line Items]
Net income	$ 3,948	[3]	$ 5,137	[4]
Other Investments in Real Estate Partnerships [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage					9.38%	35.00%
Real Estate Partnerships, Number of Properties | property	9	[5]	8	[6]
Investments in real estate partnerships	$ 177,203	[5]	$ 154,791	[6]
Income (Loss) from Equity Method Investments	3,338	[5]	18,127	[6]
Other Investments in Real Estate Partnerships [Member] | Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total assets of the Partnership	478,592	[5]	468,142	[6]
Other Investments in Real Estate Partnerships [Member] | Net Income [Member]
Schedule of Equity Method Investments [Line Items]
Net income	$ 8,574	[5]	$ 38,182	[6]
Other Investments in Real Estate Partnerships [Member] | Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	35.00%	[5]	18.38%	[6]
Other Investments in Real Estate Partnerships [Member] | Maximum [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	50.00%	[5]	50.00%	[6]

[1] On January 1, 2020, the Company purchased the remaining 70% of a property owned by the NYC partnership (Country Walk Plaza), as discussed in note 2, and therefore all earnings of this property are included in consolidated results from the date of acquisition and excluded from partnership earnings.

[2] 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.

[3] 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 $4.4 million, which is recorded within Accounts Payable and other liabilities in the Consolidated Balance Sheets.

[4] 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.

[5] In January 2020, the Company purchased an additional 16.62% interest in Town and Country Shopping Center, bringing its total ownership interest to 35%.

[6] Includes our investment in the Town and Country shopping center, which began with an initial 9.38% ownership percent in 2018, with an additional 9.0% interest acquired during 2019.