Quarterly report pursuant to Section 13 or 15(d)

Changes in Carrying Value of Goodwill (Details)

v2.4.1.9
Changes in Carrying Value of Goodwill (Details) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended 6 Months Ended
Feb. 28, 2015
Feb. 28, 2015
Goodwill [Roll Forward]    
Balance as of August 31, 2014   $ 742,770us-gaap_Goodwill
Purchase accounting adjustments   (3,157)us-gaap_GoodwillPurchaseAccountingAdjustments
Goodwill Impairment Charge (78,000)us-gaap_GoodwillImpairmentLoss (78,530)us-gaap_GoodwillImpairmentLoss
Impact of changes in foreign currency rates   (45,130)us-gaap_GoodwillTranslationAdjustments
Balance as of February 28, 2015 615,953us-gaap_Goodwill 615,953us-gaap_Goodwill
Industrial    
Goodwill [Roll Forward]    
Balance as of August 31, 2014   100,266us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= atu_IndustrialMember
Purchase accounting adjustments   (3,157)us-gaap_GoodwillPurchaseAccountingAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= atu_IndustrialMember
Goodwill Impairment Charge   0us-gaap_GoodwillImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= atu_IndustrialMember
Impact of changes in foreign currency rates   (4,681)us-gaap_GoodwillTranslationAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= atu_IndustrialMember
Balance as of February 28, 2015 92,428us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= atu_IndustrialMember 		92,428us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= atu_IndustrialMember
Energy    
Goodwill [Roll Forward]    
Balance as of August 31, 2014   350,627us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= atu_EnergyMember
Purchase accounting adjustments   0us-gaap_GoodwillPurchaseAccountingAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= atu_EnergyMember
Goodwill Impairment Charge   (78,530)us-gaap_GoodwillImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= atu_EnergyMember
Impact of changes in foreign currency rates   (29,556)us-gaap_GoodwillTranslationAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= atu_EnergyMember
Balance as of February 28, 2015 242,540us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= atu_EnergyMember 		242,540us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= atu_EnergyMember
Engineered Solutions    
Goodwill [Roll Forward]    
Balance as of August 31, 2014   291,877us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= atu_EngineeredSolutionsMember
Purchase accounting adjustments   0us-gaap_GoodwillPurchaseAccountingAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= atu_EngineeredSolutionsMember
Goodwill Impairment Charge   0us-gaap_GoodwillImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= atu_EngineeredSolutionsMember
Impact of changes in foreign currency rates   (10,893)us-gaap_GoodwillTranslationAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= atu_EngineeredSolutionsMember
Balance as of February 28, 2015 $ 280,984us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= atu_EngineeredSolutionsMember 		$ 280,984us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= atu_EngineeredSolutionsMember