Real Estate and Lending Activities - Loans - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended
	Mar. 01, 2012	Mar. 31, 2015	Mar. 01, 2012
Significant Acquisitions and Disposals [Line Items]
Amount of convertible note converted into equity interest	$ 1.7
Convertible note	5.0		5.0
Percentage of equity shares from convertible debt	9.90%	15.10%
Remaining convertible debt after conversion of part of debt		3.3
Ernest Transaction and Other Acquisitions [Member]
Significant Acquisitions and Disposals [Line Items]
Existing mortgage loans		102.5
MEDIAN Transaction [Member]
Significant Acquisitions and Disposals [Line Items]
Existing mortgage loans		$ 442.4