Equity Investments - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended			3 Months Ended	6 Months Ended	0 Months Ended	1 Months Ended
	Mar. 31, 2014	Dec. 31, 2014		Dec. 31, 2013	Jun. 30, 2014	Jun. 30, 2014	Mar. 05, 2014	Jun. 30, 2014
Schedule of Equity Method Investments [Line Items]
Discount rate	8.00%
Market rent growth rate	2.00%
Expense growth rate	2.00%
Loan receivable, stated interest rate		12.78%		11.59%
Interest bearing loan, description of variable rate basis		LIBOR plus 3%
Mortgage loans, outstanding balance		$ 24,005,000	[1]
First Priority Mortgage Loan [Member]
Schedule of Equity Method Investments [Line Items]
Debt instrument, description of variable rate basis		40.00%
Interest bearing loan, description of variable rate basis		LIBOR plus 40%
Northwest Atlanta Partners LP [Member]
Schedule of Equity Method Investments [Line Items]
Discount rate					10.80%
Terminal capitalization rate					8.50%
Market rent growth rate					2.70%
Expense growth rate					2.80%
Sealy [Member]
Schedule of Equity Method Investments [Line Items]
Investments other-than-temporarily impaired						1,660,000
Marc Realty [Member]
Schedule of Equity Method Investments [Line Items]
Interest in joint venture, gross sale price				6,000,000
Period of exercise of option granted to joint venture partner to acquire interest				2 years
Investments other-than-temporarily impaired								762,000
Mortgage loans, interest rate							6.00%
Marc Investments [Member]
Schedule of Equity Method Investments [Line Items]
Investments other-than-temporarily impaired				7,687,000
Equity interest, carrying value				14,438,000
Equity interest, fair value				6,751,000
WRT One South State Lender LP [Member]
Schedule of Equity Method Investments [Line Items]
Loan receivable, face amount		51,716,000
Loan receivable, stated interest rate		15.00%
Loan receivable, maturity period		2017-12
RE CDO Management LLC [Member]
Schedule of Equity Method Investments [Line Items]
Acquired interest in first priority mortgage loan		5.52%
Interest bearing loan, description of variable rate basis		RE CDO holds a 5.52% interest in (i) a first priority mortgage loan collateralized by land located in Las Vegas, Nevada (the “Land”), which loan bears interest at LIBOR plus 40% with a current pay rate of 7.5% and the balance accruing and compounding and which had an outstanding balance of $21,227,000 at December 31, 2013, and (ii) a second priority mortgage loan collateralized by the Land which bears interest at 10% per annum, all of which accrues, and which had an outstanding balance of $30,401,000 at December 31, 2013. The interest in the loan was acquired for $1,093,000 and RE CDO accounts for this investment on the cost recovery method.
Current pay rate		7.50%
Payment to acquire interest in mortgage loan		1,093,000
RE CDO Management LLC [Member] | First Mortgage [Member]
Schedule of Equity Method Investments [Line Items]
Mortgage loans, outstanding balance		50,113,000
RE CDO Management LLC [Member] | Original Mortgage [Member]
Schedule of Equity Method Investments [Line Items]
Mortgage loans, outstanding balance		$ 43,097,000
Mortgage loans, interest rate		10.00%
Vintage Housing Holdings [Member]
Schedule of Equity Method Investments [Line Items]
Lag in reporting period		1 month
WRT-Elad One South State Equity LP [Member]
Schedule of Equity Method Investments [Line Items]
Lag in reporting period		1 month
WRT-Fenway Wateridge LLC [Member]
Schedule of Equity Method Investments [Line Items]
Lag in reporting period		1 month
701 Seventh WRT Investor LLC [Member]
Schedule of Equity Method Investments [Line Items]
Lag in reporting period		3 months

[1] Carrying amount represents the estimated amount expected to be collected on disposition of the loan, plus contractual interest receivable at December 31, 2014.