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Investments in Real Estate Partnerships - Schedule of Investments in Real Estate Partnerships (Details) (USD $)	12 Months Ended
	Dec. 31, 2014 property	Dec. 31, 2013 property	Dec. 31, 2012	Mar. 20, 2013
Schedule of Equity Method Investments [Line Items]
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2014
Provision for impairment	$ 1,257,000us-gaap_ImpairmentOfRealEstate	$ 6,000,000us-gaap_ImpairmentOfRealEstate	$ 74,816,000us-gaap_ImpairmentOfRealEstate
Real Estate Partnerships, Number of Properties	120	126
Investments in real estate partnerships	333,167,000	358,849,000
Revenue from Related Parties	23,000,000us-gaap_RevenueFromRelatedParties	24,200,000us-gaap_RevenueFromRelatedParties	25,400,000us-gaap_RevenueFromRelatedParties
Total Assets of the Partnership	2,807,502,000	2,939,599,000
Net Income (Loss) of the Partnership	79,466,000	71,050,000	79,264,000
Income (Loss) from Equity Method Investments	31,270,000	31,718,000	23,807,000
GRI - Regency, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%	0.00%
Real Estate Partnerships, Number of Properties	74	75
Investments in real estate partnerships	247,175,000	250,118,000
Total Assets of the Partnership	1,829,116,000	1,870,660,000
Net Income (Loss) of the Partnership	33,032,000	31,705,000
Income (Loss) from Equity Method Investments	13,727,000	12,789,000
Macquarie Country Wide - Regency III, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage		0.00%	0.00%	24.95%
Real Estate Partnerships, Number of Properties		0
Investments in real estate partnerships		0
Total Assets of the Partnership		0
Net Income (Loss) of the Partnership		213,000
Income (Loss) from Equity Method Investments		53,000
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	10	10
Investments in real estate partnerships	15,916,000	16,735,000
Total Assets of the Partnership	199,427,000	204,759,000
Net Income (Loss) of the Partnership	7,173,000	8,605,000
Income (Loss) from Equity Method Investments	1,431,000	1,727,000
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	14	15
Investments in real estate partnerships	9,343,000	8,797,000
Total Assets of the Partnership	300,028,000	295,829,000
Net Income (Loss) of the Partnership	1,211,000	6,290,000
Income (Loss) from Equity Method Investments	233,000	1,274,000
Cameron Village, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%	0.00%
Real Estate Partnerships, Number of Properties	1	1
Investments in real estate partnerships	12,114,000	16,678,000
Total Assets of the Partnership	100,625,000	103,805,000
Net Income (Loss) of the Partnership	3,393,000	2,198,000
Income (Loss) from Equity Method Investments	1,008,000	662,000
RegCal, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	0.00%	0.00%
Real Estate Partnerships, Number of Properties	7	8
Investments in real estate partnerships	13,354,000	15,576,000
Total Assets of the Partnership	149,457,000	159,255,000
Net Income (Loss) of the Partnership	4,012,000	1,300,000
Income (Loss) from Equity Method Investments	966,000	332,000
Regency Retail Partners, LP [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	0	1,793,000
Total Assets of the Partnership	0	9,325,000
Net Income (Loss) of the Partnership	171,000	9,234,000
Income (Loss) from Equity Method Investments	27,000	7,749,000
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	8	8
Investments in real estate partnerships	806,000	1,391,000
Total Assets of the Partnership	115,660,000	118,865,000
Net Income (Loss) of the Partnership	2,872,000	2,387,000
Income (Loss) from Equity Method Investments	567,000	487,000
BRE Throne Holdings LLC (BRET) [Member]
Schedule of Equity Method Investments [Line Items]
Proceeds from Sale of Real Estate		321,000,000
Provision for impairment		18,100,000
Ownership Percentage		0.00%
Real Estate Partnerships, Number of Properties		0
Proceeds from Limited Partnership Investments	47,500,000
Investments in real estate partnerships		0
Total Assets of the Partnership		0
Net Income (Loss) of the Partnership		4,499,000
Income (Loss) from Equity Method Investments		4,499,000
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	34,459,000	47,761,000
Total Assets of the Partnership	113,189,000	177,101,000
Net Income (Loss) of the Partnership	27,602,000	4,619,000
Income (Loss) from Equity Method Investments	13,311,000	2,146,000
Other Investments in Real Estate Partnership [Member]
Schedule of Equity Method Investments [Line Items]
Real Estate Partnerships, Number of Properties	6	9
Equity Method Investments [Member]
Schedule of Equity Method Investments [Line Items]
Notes payable (note 9)	506,800,000
Corporate Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Significant Acquisitions and Disposals, Acquisition Costs or Sale Proceeds	43,000,000	13,600,000
Mortgage loans assumed for the acquisition of real estate	0	7,496,000
Finite-lived Intangible Assets Acquired	7,604,000	8,438,000
Acquired Finite Lived Intangible Liability Amount	$ 3,487,000	$ 332,000