Earnings Per Share (Computation Of Basic and Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	May 05, 2018	Apr. 29, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss) attributable to Macy's, Inc. shareholders	$ 139	$ 78
Net income available to common stockholders, basic	139	78
Net income available to common stockholders, diluted	$ 139	$ 78
Basic earnings per share attributable to Macy's, Inc. shareholders	$ 0.45	$ 0.26
Diluted earnings per share attributable to Macy's, Inc. shareholders	$ 0.45	$ 0.26
Average number of shares issued, basic	305.7	304.3
Shares to be issued under deferred compensation and other plans	0.9	0.7
Average number of shares outstanding, basic	306.6	305.0
Effect of dilutive securities-stock options, restricted stock and restricted stock units	2.8	1.9
Average number of shares outstanding, diluted	309.4	306.9