Liability for Estimated Costs in Excess of Estimated Receipts During Liquidation - Schedule of Changes in Liability for Estimated Costs in Excess of Estimated Receipts During Liquidation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Remeasurement of Assets and Liabilities	$ (2,581)	$ (2,756)
Liquidation Value [Member]
Business Acquisition [Line Items]
Total liability for estimated costs in excess of estimated receipts during liquidation, beginning balance	(23,186)	(29,297)
Cash Payments (Receipts)	(3,317)	(5,719)
Remeasurement of Assets and Liabilities	(3,263)	(2,141)
Consolidation		1,749
Total liability for estimated costs in excess of estimated receipts during liquidation, ending balance	(16,606)	(23,186)
Liquidation Value [Member] | Assets [Member]
Business Acquisition [Line Items]
Estimated net inflows from investments in real estate, loans receivable and secured financing receivable, beginning balance	3,392	10,523
Cash Payments (Receipts)	2,379	4,847
Remeasurement of Assets and Liabilities	(542)	978
Consolidation		1,306
Estimated net inflows from investments in real estate, loans receivable and secured financing receivable, ending balance	1,555	3,392
Liability [Member] | Liquidation Value [Member]
Business Acquisition [Line Items]
Total liability for estimated costs, beginning balance	(26,578)	(39,820)
Cash Payments (Receipts)	5,696	10,566
Remeasurement of Assets and Liabilities	2,721	3,119
Consolidation		(443)
Total liability for estimated costs, ending balance	(18,161)	(26,578)
Liability [Member] | Liquidation Value [Member] | Sales Costs [Member]
Business Acquisition [Line Items]
Total liability for estimated costs, beginning balance	(2,851)	(5,986)
Cash Payments (Receipts)	2,027	3,215
Remeasurement of Assets and Liabilities	140	363
Consolidation		(443)
Total liability for estimated costs, ending balance	(684)	(2,851)
Liability [Member] | Liquidation Value [Member] | Corporate Expenditures [Member]
Business Acquisition [Line Items]
Total liability for estimated costs, beginning balance	(23,727)	(33,834)
Cash Payments (Receipts)	3,669	7,351
Remeasurement of Assets and Liabilities	2,581	2,756
Total liability for estimated costs, ending balance	$ (17,477)	$ (23,727)