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Leases - Additional Information (Details) - USD ($)
9 Months Ended
Oct. 31, 2019
Jan. 31, 2019
Lessee Lease Description [Line Items]    
Finance lease agreements term 4 years  
Sublease expiration year 2023  
Operating leases, undiscounted future payments $ 17,200,000  
Finance lease,not yet commenced 0  
Asset retirement obligation   $ 0
Other Long-term Liabilities    
Lessee Lease Description [Line Items]    
Asset retirement obligation $ 2,800,000  
Minimum    
Lessee Lease Description [Line Items]    
Operating lease expiration year 2020  
Term of sublease arrangement 31 months  
Operating lease has not yet commenced lease term 4 years  
Maximum    
Lessee Lease Description [Line Items]    
Operating lease expiration year 2029  
Term of sublease arrangement 55 months  
Operating lease has not yet commenced lease term 5 years