Investments in Real Estate Partnerships - Schedule of Investments in Real Estate Partnerships (Details) ratio in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) property	Dec. 31, 2017 USD ($) property	Dec. 31, 2016 USD ($)
Schedule of Equity Method Investments [Line Items]
Real Estate Partnerships, Number of Properties \| property	120	115
Investments in real estate partnerships	$ 463,001	$ 386,304
Total Assets of the Partnership	3,227,831	2,885,720
Net Income (Loss) of the Partnership	129,085	139,958	$ 161,047
Income (Loss) from Equity Method Investments	$ 42,974	$ 43,341	$ 56,518
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	$ 189,381	$ 198,521
Total Assets of the Partnership	1,646,448	1,656,068
Net Income (Loss) of the Partnership	74,139	69,211
Income (Loss) from Equity Method Investments	$ 29,614	$ 27,440
Macquarie Country Wide - Regency Iii, 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
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	$ 54,250
Total Assets of the Partnership	277,626
Net Income (Loss) of the Partnership	2,239
Income (Loss) from Equity Method Investments	$ 490
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	7	6
Investments in real estate partnerships	$ 13,625	$ 7,057
Total Assets of the Partnership	141,807	130,836
Net Income (Loss) of the Partnership	6,650	18,233
Income (Loss) from Equity Method Investments	$ 1,311	$ 3,620
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	13	12
Investments in real estate partnerships	$ 38,110	$ 13,720
Total Assets of the Partnership	377,121	329,992
Net Income (Loss) of the Partnership	23,367	7,690
Income (Loss) from Equity Method Investments	$ 4,673	$ 1,530
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	$ 11,169	$ 11,784
Total Assets of the Partnership	98,633	99,808
Net Income (Loss) of the Partnership	3,177	2,917
Income (Loss) from Equity Method Investments	$ 943	$ 850
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	$ 31,235	$ 27,829
Total Assets of the Partnership	139,844	138,717
Net Income (Loss) of the Partnership	6,167	5,613
Income (Loss) from Equity Method Investments	$ 1,542	$ 1,403
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	7
Investments in real estate partnerships	$ 0	$ 0
Total Assets of the Partnership	89,524	90,900
Net Income (Loss) of the Partnership	4,685	22,299
Income (Loss) from Equity Method Investments	$ 937	$ 4,456
Other Investments in Real Estate Partnerships [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage		0.00%
Real Estate Partnerships, Number of Properties	0	0
Investments in real estate partnerships	$ 125,231	$ 74,116
Total Assets of the Partnership	456,828	154,987
Net Income (Loss) of the Partnership	8,661	11,238
Income (Loss) from Equity Method Investments	$ 3,464	$ 3,356
Minimum [Member] \| Other Investments in Real Estate Partnerships [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%
Maximum [Member] \| Other Investments in Real Estate Partnerships [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%

Real Estate Partnerships, Number of Properties

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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