Investments in Real Estate Partnerships - Balance Sheet Summarized Financial Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 BRE Throne Holdings LLC (BRET) [Member]	Dec. 31, 2012 BRE Throne Holdings LLC (BRET) [Member]	Jul. 25, 2012 BRE Throne Holdings LLC (BRET) [Member]	Dec. 31, 2013 Indian Springs at Woodlands, Ltd. [Member]	Dec. 31, 2012 Indian Springs at Woodlands, Ltd. [Member]
Schedule of Equity Method Investments [Line Items]
Document Fiscal Year Focus	2013
Investment in real estate, net	$ 2,742,591	$ 3,213,984
Acquired lease intangible assets, net	52,350	74,986
Other assets	144,658	145,984
Total assets	2,939,599	3,434,954	0	0
Notes payable	1,519,943	1,816,648
Acquired lease intangible liabilities, net	31,148	46,264
Other liabilities	66,829	70,576
Capital - Regency	468,099	518,505
Capital - Third parties	853,580	982,961
Total liabilities and capital	2,939,599	3,434,954
Impairment Losses Related to Real Estate Partnerships	(5,880)	(5,880)
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	(29,261)	(38,995)
Equity Method Summarized Financial Information, Net Book Equity in Excess of Purchase Price	(78,203)	(78,203)
Investments in real estate partnerships (note 4)	$ 358,849	$ 442,927	$ 0	$ 48,757	$ 47,500	$ 4,094	$ 0