XML 116 R101.htm IDEA: XBRL DOCUMENT v3.19.1
Valuation and Qualifying Accounts (Parenthetical) (Details) - USD ($)
Jan. 31, 2019
Jan. 31, 2018
Valuation And Qualifying Accounts Disclosure [Line Items]    
Retained earnings $ 431,180,000 $ 388,739,000
Returns | ASU 2014-09 | Adjustments    
Valuation And Qualifying Accounts Disclosure [Line Items]    
Retained earnings $ (817,000)