Quarterly report pursuant to Section 13 or 15(d)

Guarantor Subsidiaries - Additional Information (Detail)

v2.4.1.9
Guarantor Subsidiaries - Additional Information (Detail) (5.625% Senior Notes, Senior Notes, USD $)
Nov. 30, 2014
Apr. 16, 2012
5.625% Senior Notes | Senior Notes
    
Guarantor Obligations [Line Items]    
Issuance of Senior Notes $ 300,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_DebtInstrumentAxis
= atu_FivePointSixTwoFiveSeniorNotesMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember 		$ 300,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_DebtInstrumentAxis
= atu_FivePointSixTwoFiveSeniorNotesMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
Debt instrument, interest rate 5.625%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= atu_FivePointSixTwoFiveSeniorNotesMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember 		5.625%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= atu_FivePointSixTwoFiveSeniorNotesMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember