Quarterly Financial Data - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Aug. 31, 2018	Aug. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Impairment and divestiture charges	$ 73,058	$ 116,979

Impairment and other divestiture charges - relates to the additional charges related to sale of Viking (not specifically impairment of assets) - charges include impairment charges, foreign exchange, operating lease buyout of rental assets, other divestiture charges.

No definition available.

Name:	atu_Impairmentandotherdivestiturecharges
Namespace Prefix:	atu_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration