Investments in Real Estate Partnerships - Schedule of Investments in Real Estate Partnerships (Details) ratio in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) property	Dec. 31, 2015 USD ($) property	Dec. 31, 2014 USD ($)
Schedule of Equity Method Investments [Line Items]
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2016
Provision for impairment	$ 1,700
Real Estate Partnerships, Number of Properties \| property	109	118
Investments in real estate partnerships	$ 296,699	$ 306,206
Revenue from Related Parties	24,595	24,519	$ 22,983
Total Assets of the Partnership	2,608,742	2,675,385
Net Income (Loss) of the Partnership	161,047	60,748	79,466
Income (Loss) from Equity Method Investments	$ 56,518	$ 22,508	$ 31,270
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	73
Investments in real estate partnerships	$ 201,240	$ 220,099
Total Assets of the Partnership	1,676,134	1,744,017
Net Income (Loss) of the Partnership	74,758	45,761
Income (Loss) from Equity Method Investments	$ 29,791	$ 18,148
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	9
Investments in real estate partnerships	$ 9,687	$ 15,255
Total Assets of the Partnership	145,192	175,044
Net Income (Loss) of the Partnership	21,024	(1,396)
Income (Loss) from Equity Method Investments	$ 4,180	$ (278)
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	14
Investments in real estate partnerships	$ 14,750	$ 8,496
Total Assets of the Partnership	338,307	290,064
Net Income (Loss) of the Partnership	16,765	3,794
Income (Loss) from Equity Method Investments	$ 3,240	$ 755
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	$ 11,877	$ 11,857
Total Assets of the Partnership	99,967	100,124
Net Income (Loss) of the Partnership	2,326	2,195
Income (Loss) from Equity Method Investments	$ 695	$ 643
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	$ 21,516	$ 17,967
Total Assets of the Partnership	141,827	145,213
Net Income (Loss) of the Partnership	4,358	2,316
Income (Loss) from Equity Method Investments	$ 1,080	$ 576
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	8	8
Investments in real estate partnerships	$ 13,176	$ 161
Total Assets of the Partnership	109,665	112,225
Net Income (Loss) of the Partnership	5,901	4,011
Income (Loss) from Equity Method Investments	$ 1,180	$ 807
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	$ 24,453	$ 32,371
Total Assets of the Partnership	97,650	108,698
Net Income (Loss) of the Partnership	35,915	4,067
Income (Loss) from Equity Method Investments	$ 16,352	$ 1,857

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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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