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Fair Value Measurements - Additional Information (Details) - Interest Rate Swap - USD ($)
$ in Millions
3 Months Ended
Apr. 30, 2020
Jan. 31, 2020
Derivative [Line Items]    
Derivative, effective date Sep. 05, 2019  
Derivative, maturity period 5 years  
Derivative, notional value $ 30.0  
Net unrealized loss of interest rate swap $ 1.4 $ 0.0