Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Jul. 31, 2020	Jan. 31, 2020	Aug. 02, 2019
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 5	$ 5	$ 5
Preferred stock, shares authorized	5,000,000.0	5,000,000.0	5,000,000.0
Preferred stock, shares issued	0	0	0
Preferred stock, shares outstanding	0	0	0
Common stock, par value (in dollars per share)	$ 0.50	$ 0.50	$ 0.50
Common stock, shares authorized	5,600,000,000	5,600,000,000	5,600,000,000
Common stock, shares issued	756,000,000	763,000,000	776,000,000
Common stock, shares outstanding	756,000,000	763,000,000	776,000,000