Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements (Details)

v2.4.1.9
Fair Value Measurements (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2014
Mar. 31, 2014
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs    
Contingent consideration $ 727us-gaap_BusinessCombinationContingentConsiderationLiability $ 2,067us-gaap_BusinessCombinationContingentConsiderationLiability
Contingent consideration non-current 811wstl_BusinessCombinationContingentConsiderationLiabilityNonCurrent 574wstl_BusinessCombinationContingentConsiderationLiabilityNonCurrent
Recurring [Member] | Cash and cash equivalents [Member]    
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs    
Money market funds 2,111us-gaap_AssetsFairValueDisclosureRecurring
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember 		117us-gaap_AssetsFairValueDisclosureRecurring
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
Recurring [Member] | Accrued Liabilities [Member]    
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs    
Contingent consideration 727us-gaap_BusinessCombinationContingentConsiderationLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_AccruedLiabilitiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember 		2,067us-gaap_BusinessCombinationContingentConsiderationLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_AccruedLiabilitiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
Recurring [Member] | Contingent consideration non-current [Member]    
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs    
Contingent consideration non-current 811wstl_BusinessCombinationContingentConsiderationLiabilityNonCurrent
/ us-gaap_BalanceSheetLocationAxis
= wstl_ContingentConsiderationPayableNetMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember 		574wstl_BusinessCombinationContingentConsiderationLiabilityNonCurrent
/ us-gaap_BalanceSheetLocationAxis
= wstl_ContingentConsiderationPayableNetMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Cash and cash equivalents [Member]    
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs    
Money market funds 2,111us-gaap_AssetsFairValueDisclosureRecurring
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember 		117us-gaap_AssetsFairValueDisclosureRecurring
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
Recurring [Member] | Unobservable Inputs (Level 3) [Member] | Accrued Liabilities [Member]    
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs    
Contingent consideration 727us-gaap_BusinessCombinationContingentConsiderationLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_AccruedLiabilitiesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember 		2,067us-gaap_BusinessCombinationContingentConsiderationLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_AccruedLiabilitiesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
Recurring [Member] | Unobservable Inputs (Level 3) [Member] | Contingent consideration non-current [Member]    
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs    
Contingent consideration non-current $ 811wstl_BusinessCombinationContingentConsiderationLiabilityNonCurrent
/ us-gaap_BalanceSheetLocationAxis
= wstl_ContingentConsiderationPayableNetMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember 		$ 574wstl_BusinessCombinationContingentConsiderationLiabilityNonCurrent
/ us-gaap_BalanceSheetLocationAxis
= wstl_ContingentConsiderationPayableNetMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember