Plan of Liquidation - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended	15 Months Ended	52 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2017	Feb. 28, 2017	Aug. 05, 2015	Nov. 30, 2016	Mar. 31, 2016	Mar. 31, 2012	Dec. 15, 2011	Mar. 31, 2011
Class of Warrant or Right [Line Items]
Allowed General Unsecured Claims										$ 29,771,000,000
Disputed General Unsecured Claims	$ 0		$ 0							8,154,000,000
Total aggregate amount of general unsecured claims, both allowed and disputed inclusive of potential Term Loan Avoidance Action Claims										39,425,000,000
Reserve for remaining Disputed General Unsecured Claims	50,000,000		50,000,000
Disputed General Unsecured Claims resolved or disallowed			20,000,000
Amount of Term Loan Avoidance Action										1,500,000,000
Dividends received					$ 24,700,000
Contribution from MLC										52,700,000
Initial Reporting Cash										$ 5,700,000
Appropriated Distributable Cash				$ 22,000,000
Distributable Cash set aside for projected Trust fees, costs and expenses	29,800,000		29,800,000
Distributable Cash set aside for potential Taxes on Distribution	0		0
Residual Wind-Down Assets	11,900,000		11,900,000						$ 42,800,000
Cash received to fund Avoidance Action Defense Costs									1,400,000
Residual wind-down assets transferred benefit in prepaid expenses									2,800,000
Avoidance action defense costs in excess of corresponding cash	29,400,000		29,400,000
Net additions (reductions) in reserves for Residual Wind-Down Claims and Costs	(6,200,000)	$ 6,500,000	200,000
Expected Residual Wind-Down Claims and Costs	11,900,000		11,900,000
Cash received for funding Indenture Trustee Fiscal and Paying Agent Costs and Reporting Costs									3,400,000
Cash received for indenture trustee and paying agent costs									1,400,000
Cash received for reporting cash									2,000,000
New GM Securities [Member]
Class of Warrant or Right [Line Items]
Aggregate sales of new GM Securities to fund costs and expenses					61,700,000
Aggregate dividend cash associated with sales of New GM Securities to fund costs					$ 200,000
Cash and Cash Equivalents and Marketable Securities [Member]
Class of Warrant or Right [Line Items]
Remaining Administrative Fund aggregated	1,743,000		1,743,000				$ 8,226,000
Remaining Administrative Fund Returned to DIP Lenders						$ 6,000,000
Aggregate Other Administrative Cash	14,541,000		14,541,000				13,533,000
Residual Wind-Down Assets	11,713,000		11,713,000				22,003,000		$ 40,000,000
Funds for Indenture Trustee/Fiscal Paying Agent Costs	226,000		226,000				$ 311,000
Deposits and Other Assets [Member]
Class of Warrant or Right [Line Items]
Residual Wind-Down Assets	$ 200,000		$ 200,000
New GM Series A Warrants [Member]
Class of Warrant or Right [Line Items]
Distributable assets number of securities called by warrants										136,363,635
Exercise price per share										$ 10.00
Warrants expiration date			Jul. 10, 2016
Number of securities sold to fund costs and expenses					948,887
New GM Series B Warrants [Member]
Class of Warrant or Right [Line Items]
Distributable assets number of securities called by warrants										136,363,635
Exercise price per share										$ 18.33
Warrants expiration date			Jul. 10, 2019
Number of securities sold to fund costs and expenses					948,887
New GM Common Stock [Member]
Class of Warrant or Right [Line Items]
Distributable assets number of securities										150,000,000
Securities authorized for sale								$ 13,700,000
Number of securities sold to fund costs and expenses					1,043,801