XML 90 R73.htm IDEA: XBRL DOCUMENT
v3.5.0.2

Business Segment, Geographic and Customer Information - Additional Information (Detail) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Feb. 29, 2016 USD ($) | Feb. 29, 2016 USD ($) | Aug. 31, 2016 USD ($) Segment | Aug. 31, 2015 USD ($) | Aug. 31, 2014 USD ($)
Segment Reporting Information [Line Items] |  |  |  |  |
Number of reportable segments | Segment |  |  | 3 |  |
Impairment charge |  | $ 186,511 | $ 186,511 | $ 84,353 | $ 0
Largest customer sales in fiscal year, percent |  |  | 3.00% |  |
Export sales from domestic operation, as a percentage of total net sales |  |  | 6.30% |  |
Percentage of Product Sales to Consolidated Net Sales |  |  | 80.00% |  |
Energy |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Impairment charge |  |  | $ 140,938 | $ 84,353 |
Engineered Solutions |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Impairment charge | $ 45,700 |  |  |  |

X
- Definition Percentage Of Export Sales From Domestic To Total Net Sales + References No definition available. + Details
Name: | atu_PercentageOfExportSalesFromDomesticToTotalNetSales
Namespace Prefix: | atu_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of Product Sales to Consolidated Net Sales + References No definition available. + Details
Name: | atu_PercentageofProductSalestoConsolidatedNetSales
Namespace Prefix: | atu_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Sales Percentage Represented By Major Customers + References No definition available. + Details
Name: | atu_SalesPercentageRepresentedByMajorCustomers
Namespace Prefix: | atu_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=51824106&loc=d3e2420-110228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 + Details
Name: | us-gaap_AssetImpairmentCharges
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References No definition available. + Details
Name: | us-gaap_NumberOfReportableSegments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_SegmentReportingInformationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=atu_EnergyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=atu_EngineeredSolutionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |