Stockholders' Equity - Textuals (Details) - shares	3 Months Ended		9 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2019	Oct. 31, 2018
Stockholders' Equity [Abstract]
Common stock, shares issued	0	117,774	8,851	137,050
Treasury stock, shares utilized of equity awards	80,353	58,790	435,703	106,043