Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation (Details Textual)

v2.4.0.6
Stock-Based Compensation (Details Textual) (USD $)
12 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Mar. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
The fair value of each option was estimated on the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions:
 
Fiscal Year Ended March 31
 
2013
 
2012
 
2011
Input assumptions:
 
 
 
 
 
Expected volatility
49
%
 
70
%
 
71
%
Risk-free interest rate
0.7
%
 
1.4
%
 
1.6
%
Expected life
5 years

 
5 years

 
5 years

Expected dividend yield
%
 
%
 
%
Output weighted-average grant-date fair value
$
0.89

 
$
1.93

 
$
1.12

   
Proceeds from stock options exercised $ 87,000 $ 1,684,000 $ 2,616,000
Repurchase of Subsidiary Stock Options   117,000 36,000
2004 Stock Incentive Plan [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Allocated Share-based Compensation Expense 1,407,000 1,201,000 881,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant 4,824,090    
2004 Stock Incentive Plan [Member] | Stock Options [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting schedule of equal annual installments over four years 4 years    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term 2 years 9 months 18 days    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term 2 years 9 months 18 days 3 years 3 months 18 days  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price $ 2.15    
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term 5 years 5 years 5 years
Allocated Share-based Compensation Expense 200,000 300,000 400,000
Proceeds from stock options exercised 87,000 1,684,000 2,616,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized 200,000    
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition 2 years 8 months    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value 200,000 1,300,000 900,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period 157,807    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term 2 years 2 months 12 days    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value 867,000 [1]    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value 726,000 [1]    
2004 Stock Incentive Plan [Member] | Stock Options [Member] | Minimum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock Option Contractual Life from Grant Date 7 years    
2004 Stock Incentive Plan [Member] | Stock Options [Member] | Maximum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock Option Contractual Life from Grant Date 10 years    
2004 Stock Incentive Plan [Member] | Restricted Stock [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting schedule of equal annual installments over four years 4 years    
Allocated Share-based Compensation Expense 600,000 500,000 100,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized 700,000    
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition 1 year 7 months 6 days    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period 70,000 70,000 90,000
2004 Stock Incentive Plan [Member] | Restricted Stock Units (RSUs) [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting schedule of equal annual installments over four years 4 years    
Allocated Share-based Compensation Expense 600,000 300,000 400,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized 1,800,000    
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition 2 years 7 months 6 days    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period 530,000 500,000 620,000
2004 Stock Incentive Plan [Member] | Performance Stock Units (PSUs) [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period     620,000
2004 Stock Incentive Plan [Member] | Performance Stock Units (PSUs) [Member] | Maximum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Conversion Ratio     1.40
2004 Stock Incentive Plan [Member] | Performance Stock Units (PSUs) [Member] | Scenario, Actual [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Conversion Ratio     1.40
Subsidiary Issuer [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Allocated Share-based Compensation Expense     63,000
Repurchase of Subsidiary Stock Options   $ 117,000 $ 36,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period     732,191
[1] The intrinsic value for the stock options is calculated based on the difference between the exercise price of the underlying awards and the average of the high and low Westell Technologies’ stock price as of the reporting date.