XML 87 R38.htm IDEA: XBRL DOCUMENT v2.4.1.9
Overview - Additional Information (Detail)
 3 Months Ended
Mar. 31, 2015
Product
Customer
Employee
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]  
Transmission product lines 13alsn_TransmissionProductLines
Worldwide independent distributor and dealer locations 1,400alsn_WorldwideIndependentDistributorAndDealerLocations
Number of employees 2,700alsn_NumberOfEmployees
Sales Revenue, Net | North America | Geographic Concentration Risk  
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]  
Concentration of risk, percentage 80.00%us-gaap_ConcentrationRiskPercentage1
/ us-gaap_ConcentrationRiskByBenchmarkAxis
= us-gaap_SalesRevenueNetMember
/ us-gaap_ConcentrationRiskByTypeAxis
= us-gaap_GeographicConcentrationRiskMember
/ us-gaap_StatementGeographicalAxis
= us-gaap_NorthAmericaMember