XML 85 R80.htm IDEA: XBRL DOCUMENT v2.4.0.6
Stock and Stock Option Plans - Narrative (Detail) (USD $)
12 Months Ended
Jan. 31, 2013
Jan. 31, 2012
Jan. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of shares available to be granted as stock options 558,714    
Stock repurchased and subsequently cancelled, shares   5,382 5,441
Compensation cost $ 2,924,000 $ 3,796,000 $ 3,499,000
Income tax benefit 1,140,000 1,480,000 1,365,000
Terms of options granted 10 years    
Weighted average fair value at the date of grant for the options granted $ 10.93 $ 18.70 $ 16.08
Stock Options [Member] | Minimum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 1 month    
Stock Options [Member] | Maximum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 5 years    
Nonvested Shares [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Compensation cost $ 905,000 $ 1,655,000 $ 1,057,000
Nonvested Shares [Member] | Minimum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 1 year    
Nonvested Shares [Member] | Maximum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 5 years