Stockholders' Equity - Additional Information (Details) - Common Stock Repurchase Program - $ / shares shares in Millions	3 Months Ended		9 Months Ended
	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2021	Oct. 31, 2020
Class of Stock [Line Items]
Common stock repurchased and retired (in shares)	1.0	0.8	1.7	2.1
Repurchased shares of its common stock on the open market, average repurchase price per share (in usd per share)	$ 292.91	$ 231.26	$ 286.95	$ 185.69
Common stock shares remained available for repurchase under repurchase plans (in shares)	10.4	12.6	10.4	12.6