Investments in Real Estate Partnerships - Schedule of Investments in Real Estate Partnerships (Details) ratio in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) property	Dec. 31, 2016 USD ($) property	Dec. 31, 2015 USD ($)
Schedule of Equity Method Investments [Line Items]
Current Fiscal Year End Date	--12-31
Real Estate Partnerships, Number of Properties \| property	115	109
Investments in real estate partnerships	$ 386,304	$ 296,699
Total Assets of the Partnership	2,885,720	2,608,742
Net Income (Loss) of the Partnership	139,958	161,047	$ 60,748
Income (Loss) from Equity Method Investments	$ 43,341	$ 56,518	$ 22,508
GRI - Regency, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%	0.00%
Real Estate Partnerships, Number of Properties \| property	70	70
Investments in real estate partnerships	$ 198,521	$ 201,240
Total Assets of the Partnership	1,656,068	1,676,134
Net Income (Loss) of the Partnership	69,211	74,758
Income (Loss) from Equity Method Investments	$ 27,440	$ 29,791
Equity One JV Portfolio, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%
Real Estate Partnerships, Number of Properties \| property	6
Investments in real estate partnerships	$ 53,277
Total Assets of the Partnership	284,412
Net Income (Loss) of the Partnership	2,757
Income (Loss) from Equity Method Investments	$ 686
Columbia Regency Retail Partners, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%	0.00%
Real Estate Partnerships, Number of Properties \| property	6	7
Investments in real estate partnerships	$ 7,057	$ 9,687
Total Assets of the Partnership	130,836	145,192
Net Income (Loss) of the Partnership	18,233	21,024
Income (Loss) from Equity Method Investments	$ 3,620	$ 4,180
Columbia Regency Partners II, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%	0.00%
Real Estate Partnerships, Number of Properties \| property	12	12
Investments in real estate partnerships	$ 13,720	$ 14,750
Total Assets of the Partnership	329,992	338,307
Net Income (Loss) of the Partnership	7,690	16,765
Income (Loss) from Equity Method Investments	$ 1,530	$ 3,240
Cameron Village, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%	0.00%
Real Estate Partnerships, Number of Properties \| property	1	1
Investments in real estate partnerships	$ 11,784	$ 11,877
Total Assets of the Partnership	99,808	99,967
Net Income (Loss) of the Partnership	2,917	2,326
Income (Loss) from Equity Method Investments	$ 850	$ 695
RegCal, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%	0.00%
Real Estate Partnerships, Number of Properties \| property	7	7
Investments in real estate partnerships	$ 27,829	$ 21,516
Total Assets of the Partnership	138,717	141,827
Net Income (Loss) of the Partnership	5,613	4,358
Income (Loss) from Equity Method Investments	$ 1,403	$ 1,080
US Regency Retail 1, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%	0.00%
Real Estate Partnerships, Number of Properties \| property	7	8
Investments in real estate partnerships	$ 0	$ 13,176
Total Assets of the Partnership	90,900	109,665
Net Income (Loss) of the Partnership	22,299	5,901
Income (Loss) from Equity Method Investments	$ 4,456	$ 1,180
Other Investments in Real Estate Partnerships [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%	0.00%
Real Estate Partnerships, Number of Properties	0	0
Investments in real estate partnerships	$ 74,116	$ 24,453
Total Assets of the Partnership	154,987	97,650
Net Income (Loss) of the Partnership	11,238	35,915
Income (Loss) from Equity Method Investments	$ 3,356	$ 16,352

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The amount of assets reported by an equity method investment of the entity.

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The amount of net income (loss) reported by an equity method investment of the entity.

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