Annual report pursuant to Section 13 and 15(d)

Goodwill and Intangible Assets (Details)

v2.4.1.9
Goodwill and Intangible Assets (Details) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended 12 Months Ended
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2015
Mar. 31, 2014
Mar. 31, 2013
Goodwill [Line Items]            
Goodwill       $ 0us-gaap_Goodwill $ 31,102us-gaap_Goodwill [1] $ 0us-gaap_Goodwill
Goodwill, Acquired During Period         31,102us-gaap_GoodwillAcquiredDuringPeriod [1]  
Goodwill impairment (20,547)us-gaap_GoodwillImpairmentLoss (10,555)us-gaap_GoodwillImpairmentLoss   (31,102)us-gaap_GoodwillImpairmentLoss   (2,884)us-gaap_GoodwillImpairmentLoss
Goodwill, Transfers     0us-gaap_GoodwillTransfers      
Kentrox [Member]            
Goodwill [Line Items]            
Goodwill       0us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_KentroxMember 		10,555us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_KentroxMember 		 
Goodwill, Acquired During Period         10,555us-gaap_GoodwillAcquiredDuringPeriod
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_KentroxMember 		 
Goodwill, Transfers     (10,555)us-gaap_GoodwillTransfers
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_KentroxMember 		     
CSI [Member]            
Goodwill [Line Items]            
Goodwill       0us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_CSIMember 		20,547us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_CSIMember 		[1]  
Goodwill, Acquired During Period         20,547us-gaap_GoodwillAcquiredDuringPeriod
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_CSIMember 		[1]  
Goodwill, Transfers     (20,547)us-gaap_GoodwillTransfers
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_CSIMember 		     
CSG [Member]            
Goodwill [Line Items]            
Goodwill       0us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_CSGMember 		0us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_CSGMember 		0us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_CSGMember
Goodwill, Acquired During Period         0us-gaap_GoodwillAcquiredDuringPeriod
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_CSGMember 		 
Goodwill impairment       (10,555)us-gaap_GoodwillImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_CSGMember 		   
Goodwill, Transfers     10,555us-gaap_GoodwillTransfers
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_CSGMember 		     
IBW [Member]            
Goodwill [Line Items]            
Goodwill   20,500us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_IBWMember 		  0us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_IBWMember 		0us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_IBWMember 		0us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_IBWMember
Goodwill, Acquired During Period         0us-gaap_GoodwillAcquiredDuringPeriod
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_IBWMember 		 
Goodwill impairment       (20,547)us-gaap_GoodwillImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_IBWMember 		   
Goodwill, Transfers     $ 20,547us-gaap_GoodwillTransfers
/ us-gaap_StatementBusinessSegmentsAxis
= wstl_IBWMember 		     
[1] Certain amounts have been adjusted to reflect measurement period adjustments related to the CSI acquisition (see Note 2).