Real Estate Fund Investments - Additional Information (Details)	3 Months Ended
	Mar. 31, 2016 USD ($)
Investment Holdings [Line Items]
Aggregate committed capital	$ 580,200,000
Committed capital invested	166,560,000
Investments in unconsolidated real estate funds	26,880,000
Loss from the investments in unconsolidated real estate funds	326,000
Residential Development Fund [Member]
Investment Holdings [Line Items]
Aggregate committed capital	135,600,000
Committed capital invested	69,000,000
Property Funds [Member]
Investment Holdings [Line Items]
Investments in unconsolidated real estate funds	23,132,000
Loss from the investments in unconsolidated real estate funds	345,000
Alternative Investment Funds [Member]
Investment Holdings [Line Items]
Investments in unconsolidated real estate funds	3,748,000
Loss from the investments in unconsolidated real estate funds	$ 19,000