Quarterly report pursuant to Section 13 or 15(d)

Notes Payable - Additional Information (Detail)

v3.3.0.814
Notes Payable - Additional Information (Detail) - USD ($)
9 Months Ended
Oct. 31, 2015
Jan. 31, 2015
Nov. 01, 2014
Line of Credit Facility [Line Items]      
Additional credit available under the revolving facility with consent by each lender and other conditions $ 50,000,000    
Interest rate on outstanding borrowing under facility LIBOR plus 1.50%    
Percentage of unused Line of Credit Facility Fee 0.20%    
Outstanding debt under credit facility $ 0 $ 0 $ 0
Revolving Credit Facility [Member]      
Line of Credit Facility [Line Items]      
Credit facility, maximum borrowing capacity 200,000,000    
Subfacility for Standby Letters of Credit [Member]      
Line of Credit Facility [Line Items]      
Credit facility, maximum borrowing capacity $ 10,000,000