CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS (Relationships with RRE Opportunity REIT, Atlas Energy, L.P. and 1845 Walnut Associates Ltd.) (Details) (USD $)			0 Months Ended				1 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Jun. 17, 2011 Resource Real Estate Opportunity REIT Inc [Member]	Sep. 30, 2012 Resource Real Estate Opportunity REIT Inc [Member]	Sep. 30, 2012 Atlas Energy, L.P. [Member]	Sep. 30, 2012 Eighteen Forty Five Walnut Associates Ltd [Member]	Oct. 31, 2012 Eighteen Forty Five Walnut Associates Ltd [Member] Subsequent Event [Member] sqft
Related Party Transaction [Line Items]
Receivables from managed entities and related parties, net	$ 34,418,000	$ 52,117,000		$ 138,000	$ 52,000
Notes receivable, related party			1,400,000
Interest rate (in hundredths)			6.50%
Maturity term			6 months
Equity interest, ownership percentage						5.00%
Lease term							10 years
Area of real estate property							28,930
Payments for tenant improvements							$ 1,400,000
Potential extended additional term							5 years