Goodwill and Intangibles - Schedule of Carrying Amounts of Intangible Assets (Parenthetical) (Detail) - Trade Names [Member] - AutoAnything's and Interamerican Motor Corporation [Member] - USD ($) $ in Millions	3 Months Ended
	Feb. 10, 2018	Aug. 25, 2018
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Impairment charge	$ 26.9
Accumulated impairment		$ 31.0