Annual report pursuant to Section 13 and 15(d)

Segment Information (Details 1)

v2.4.1.9
Segment Information (Details 1)
12 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Mar. 31, 2013
Verizon [Member]      
Revenue, Major Customer [Line Items]      
Percentage Of Net Revenue 30.50%wstl_PercentageOfNetRevenue
/ us-gaap_MajorCustomersAxis
= wstl_VerizonMember
23.90%wstl_PercentageOfNetRevenue
/ us-gaap_MajorCustomersAxis
= wstl_VerizonMember
17.10%wstl_PercentageOfNetRevenue
/ us-gaap_MajorCustomersAxis
= wstl_VerizonMember
Telamon [Member]      
Revenue, Major Customer [Line Items]      
Percentage Of Net Revenue 5.80%wstl_PercentageOfNetRevenue
/ us-gaap_MajorCustomersAxis
= wstl_TelamonMember
30.30%wstl_PercentageOfNetRevenue
/ us-gaap_MajorCustomersAxis
= wstl_TelamonMember
12.40%wstl_PercentageOfNetRevenue
/ us-gaap_MajorCustomersAxis
= wstl_TelamonMember
Time Warner Cable [Member]      
Revenue, Major Customer [Line Items]      
Percentage Of Net Revenue 2.60%wstl_PercentageOfNetRevenue
/ us-gaap_MajorCustomersAxis
= wstl_TimeWarnerCableMember
2.30%wstl_PercentageOfNetRevenue
/ us-gaap_MajorCustomersAxis
= wstl_TimeWarnerCableMember
10.40%wstl_PercentageOfNetRevenue
/ us-gaap_MajorCustomersAxis
= wstl_TimeWarnerCableMember