Quarterly Results (unaudited) (Unaudited Quarterly Results) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
Jan. 28, 2017	Oct. 29, 2016	Jul. 30, 2016	Apr. 30, 2016	Jan. 30, 2016	Oct. 31, 2015	Aug. 01, 2015	May 02, 2015	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Quarterly Financial Data [Abstract]
Net sales	$ 8,515	$ 5,626	$ 5,866	$ 5,771	$ 8,869	$ 5,874	$ 6,104	$ 6,232	$ 25,778	$ 27,079	$ 28,105
Cost of sales	(5,251)	(3,386)	(3,468)	(3,516)	(5,549)	(3,537)	(3,610)	(3,800)	(15,621)	(16,496)	(16,863)
Gross margin	3,264	2,240	2,398	2,255	3,320	2,337	2,494	2,432	10,157	10,583	11,242
Selling, general and administrative expenses	(2,202)	(2,071)	(2,026)	(1,966)	(2,207)	(1,968)	(2,058)	(2,023)	(8,265)	(8,256)	(8,355)
Impairments, store closing and other costs	(230)	0	(249)	0	(177)	(111)	0	0	(479)	(288)	(87)
Settlement charges	(17)	(62)	(6)	(13)					(98)	0	0
Net income attributable to Macy's, Inc. shareholders	$ 475	$ 17	$ 11	$ 116	$ 544	$ 118	$ 217	$ 193	$ 619	$ 1,072	$ 1,526
Basic earnings per share attributable to Macy's, Inc. shareholders	$ 1.56	$ 0.05	$ 0.03	$ 0.37	$ 1.74	$ 0.36	$ 0.65	$ 0.57	$ 2.01	$ 3.26	$ 4.30
Diluted earnings per share attributable to Macy's, Inc. shareholders	$ 1.54	$ 0.05	$ 0.03	$ 0.37	$ 1.73	$ 0.36	$ 0.64	$ 0.56	$ 1.99	$ 3.22	$ 4.22

The amount of asset impairments and other costs

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The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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Amount of net gain (loss) recognized in net periodic benefit cost as a result of an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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