Investments in Real Estate Partnerships - Schedule of Investments in Real Estate Partnerships (Details) ratio in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($) property	Dec. 31, 2014 USD ($) property	Dec. 31, 2013 USD ($)
Schedule of Equity Method Investments [Line Items]
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2015
Real Estate Partnerships, Number of Properties \| property	118	120
Investments in real estate partnerships	$ 306,206	$ 333,167
Revenue from Related Parties	24,519	22,983	$ 24,153
Total Assets of the Partnership	2,675,385	2,807,502
Net Income (Loss) of the Partnership	60,748	79,466	71,050
Income (Loss) from Equity Method Investments	$ 22,508	$ 31,270	$ 31,718
GRI - Regency, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%	0.00%
Real Estate Partnerships, Number of Properties \| property	73	74
Investments in real estate partnerships	$ 220,099	$ 247,175
Total Assets of the Partnership	1,744,017	1,829,116
Net Income (Loss) of the Partnership	45,761	33,032
Income (Loss) from Equity Method Investments	$ 18,148	$ 13,727
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	9	10
Investments in real estate partnerships	$ 15,255	$ 15,916
Total Assets of the Partnership	175,044	199,427
Net Income (Loss) of the Partnership	(1,396)	7,173
Income (Loss) from Equity Method Investments	$ (278)	$ 1,431
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	14	14
Investments in real estate partnerships	$ 8,496	$ 9,343
Total Assets of the Partnership	290,064	300,028
Net Income (Loss) of the Partnership	3,794	1,211
Income (Loss) from Equity Method Investments	$ 755	$ 233
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	$ 11,857	$ 12,114
Total Assets of the Partnership	100,124	100,625
Net Income (Loss) of the Partnership	2,195	3,393
Income (Loss) from Equity Method Investments	$ 643	$ 1,008
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	$ 17,967	$ 13,354
Total Assets of the Partnership	145,213	149,457
Net Income (Loss) of the Partnership	2,316	4,012
Income (Loss) from Equity Method Investments	$ 576	$ 966
US Regency Retail I, 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	$ 161	$ 806
Total Assets of the Partnership	112,225	115,660
Net Income (Loss) of the Partnership	4,011	2,872
Income (Loss) from Equity Method Investments	$ 807	$ 567
Other Investments in Real Estate Partnerships [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%	0.00%
Investments in real estate partnerships	$ 32,371	$ 34,459
Total Assets of the Partnership	108,698	113,189
Net Income (Loss) of the Partnership	4,067	27,773
Income (Loss) from Equity Method Investments	$ 1,857	$ 13,338
Other Investments in Real Estate Partnership [Member]
Schedule of Equity Method Investments [Line Items]
Real Estate Partnerships, Number of Properties \| property	6	6
Corporate Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Mortgage loans assumed for the acquisition of real estate		$ 0
Finite-lived Intangible Assets Acquired		7,604
Acquired Finite Lived Intangible Liability Amount		$ 3,487

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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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