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Intangible Assets and Goodwill - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Jan. 31, 2020
Jan. 31, 2019
Jan. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]      
Amortization expense $ 10.1 $ 7.0 $ 7.8