XML 34 R21.htm IDEA: XBRL DOCUMENT v3.8.0.1
Basis of Presentation and Summary of Significant Accounting Policies (Tables)
 12 Months Ended
Jan. 31, 2018
Accounting Policies [Abstract]  
Schedule of Changes in Allowance for Doubtful Accounts
The following table presents the changes in the allowance for doubtful accounts:
 
 
Year Ended January 31,
 
2016
 
2017
 
2018
 
(in thousands) 
Allowance for doubtful accounts, beginning balance
$
210

 
$
944

 
$
2,000

Provision, net
918

 
1,394

 
482

Writeoffs
(184
)
 
(338
)
 
(1,420
)
Allowance for doubtful accounts, ending balance
$
944

 
$
2,000

 
$
1,062