Earnings Per Share (Computation Of Basic and Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Oct. 28, 2017	Oct. 29, 2016	Oct. 28, 2017	Oct. 29, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss) attributable to Macy's, Inc. shareholders	$ 36	$ 17	$ 222	$ 144
Net income available to common stockholders, basic	36	17	222	144
Net income available to common stockholders, diluted	$ 36	$ 17	$ 222	$ 144
Basic earnings per share attributable to Macy's, Inc. shareholders	$ 0.12	$ 0.05	$ 0.73	$ 0.46
Diluted earnings per share attributable to Macy's, Inc. shareholders	$ 0.12	$ 0.05	$ 0.73	$ 0.46
Average number of shares issued, basic	304.6	307.5	304.5	308.6
Shares to be issued under deferred compensation and other plans	0.9	0.9	0.8	0.9
Average number of shares outstanding, basic	305.5	308.4	305.3	309.5
Effect of dilutive securities-stock options, restricted stock and restricted stock units	1.0	2.2	1.3	2.3
Average number of shares outstanding, diluted	306.5	310.6	306.6	311.8