Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Additional Information (Detail)

v2.4.0.8
Stock-Based Compensation - Additional Information (Detail) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 6 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Sep. 30, 2014
Sep. 30, 2013
Employee Stock Purchase Plan [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock based compensation expense $ 13 $ 13 $ 30 $ 28
Income tax benefit to stock based compensation 4 4 10 9
Discounted purchase price of common stock percentage on fair market value 85.00% 85.00% 85.00% 85.00%
Shares approved for purchase under ESPP 200   200  
Restricted Stock [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock based compensation expense 163 134 269 314
Income tax benefit to stock based compensation $ 57 $ 47 $ 94 $ 110
Amended And Restated 2000 Incentive Plan [Member] | Employee Stock Option [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock options maximum term 10 years 10 years 10 years 10 years
Stock option awards granted     0 0
Amended And Restated 2000 Incentive Plan [Member] | Employee Stock Option [Member] | Maximum [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares authorized 1,375   1,375  
Amended And Restated 2000 Incentive Plan [Member] | Restricted Stock [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Restricted stock awards     30 32
Amended And Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Time Vested Restricted Stock [Member] | Director [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Restricted stock awards 2 0 7 6
Share-based compensation vesting percentage 100.00% 100.00% 100.00% 100.00%
Vesting period 1 year 1 year 1 year 1 year
Amended And Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Time Vested Restricted Stock [Member] | Officers and Key Employees [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Restricted stock awards     11 12
Share-based compensation vesting percentage     33.33% 33.33%
Vesting period     3 years 3 years
Amended And Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Performance Vested Restricted Stock [Member] | Officer [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Restricted stock awards     12 14
Share-based compensation vesting percentage     100.00% 100.00%
Vesting period     3 years 3 years
Amended And Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Maximum [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares authorized 250   250