Liquidating Distributions - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	Sep. 30, 2014
Distribution Made to Limited Partner [Line Items]
Cash distributions payable	$ 3.4
New GM Common Stock [Member]
Distribution Made to Limited Partner [Line Items]
GUC Trust distribution obligation	3,749,598
New GM Series A Warrants [Member]
Distribution Made to Limited Partner [Line Items]
GUC Trust distribution obligation	3,408,618
New GM Series B Warrants [Member]
Distribution Made to Limited Partner [Line Items]
GUC Trust distribution obligation	3,408,618