GENERAL - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Property	Sep. 30, 2012	Dec. 31, 2012
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Legal settlements received	$ 3,126,000		$ 3,126,000
Number of real estate properties held for sale			131
Real estate held for sale, net	30,061,000		30,061,000		25,340,000
Impairment charges	3,265,000	7,406,000	7,717,000	10,552,000
Description of tax liability based upon IRS ruling			If we do not receive a favorable ruling on this matter we may incur a tax liability equal to (A) to the greater of the amount by which we fail to meet either the 95% or 75% income test multiplied (B) by the fraction the numerator of which is our net income (determined in a certain manner) and the denominator of which is our gross income for the tax year.
Litigation Funding Agreement [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Legal settlements received	25,096,000
Reit Qualification Test Gross Income Percentage One [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
REIT's gross income			95.00%
Reit Qualification Test Gross Income Percentage Two [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
REIT's gross income			75.00%
Level 3 inputs [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Assumed holding periods for unobservable inputs			15 years
Assumed annual average rent increases for unobservable inputs			2.00%
Rate of income capitalization for unobservable inputs			8.00%
Cash flows discounted rate for unobservable inputs			7.00%
Level 3 inputs [Member] | Fair Value, Measurements, Nonrecurring [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Accounts Receivable, Fair Value Disclosure					2,972,000
Impaired real estate assets measured at fair value	$ 7,173,000		$ 7,173,000		$ 4,967,000