Stockholders' Equity (Detail) - $ / shares	Apr. 30, 2020	Jan. 31, 2020	Jul. 22, 2019
Equity [Abstract]
Common stock, shares authorized (in shares)	500,000,000	500,000,000	500,000,000
Common stock, par value per share (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Common stock, shares issued (in shares)	37,599,441	36,610,763
Common stock, shares outstanding (in shares)	37,599,441	36,610,763
Preferred stock, shares authorized (in shares)			20,000,000
Preferred stock, par value (in dollars per share)			$ 0.01
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0