Segment Information - Net Sales by Brand and Region (Details) - USD ($) $ in Millions		3 Months Ended								12 Months Ended
		Feb. 03, 2018	Oct. 28, 2017	Jul. 29, 2017	Apr. 29, 2017	Jan. 28, 2017	Oct. 29, 2016	Jul. 30, 2016	Apr. 30, 2016	Feb. 03, 2018		Jan. 28, 2017		Jan. 30, 2016
Segment Reporting Information [Line Items]
Net sales		$ 4,778	$ 3,838	$ 3,799	$ 3,440	$ 4,429	$ 3,798	$ 3,851	$ 3,438	$ 15,855		$ 15,516		$ 15,797
Percentage Of Net Sales										100.00%		100.00%		100.00%
U.S.
Segment Reporting Information [Line Items]
Net sales	[1]									$ 12,568		$ 11,989		$ 12,213
Percentage Of Net Sales										80.00%		77.00%		77.00%
Canada
Segment Reporting Information [Line Items]
Net sales										$ 1,173		$ 1,084		$ 1,047
Percentage Of Net Sales										7.00%		7.00%		7.00%
Europe
Segment Reporting Information [Line Items]
Net sales										$ 641		$ 689		$ 797
Percentage Of Net Sales										4.00%		5.00%		5.00%
Asia
Segment Reporting Information [Line Items]
Net sales										$ 1,263		$ 1,544		$ 1,521
Percentage Of Net Sales										8.00%		10.00%		10.00%
Other Regions
Segment Reporting Information [Line Items]
Net sales										$ 210		$ 210		$ 219
Percentage Of Net Sales										1.00%		1.00%		1.00%
Gap Global
Segment Reporting Information [Line Items]
Net sales										$ 5,318		$ 5,455		$ 5,751
Gap Global | U.S.
Segment Reporting Information [Line Items]
Net sales	[1]									3,065		3,113		3,303
Gap Global | Canada
Segment Reporting Information [Line Items]
Net sales										398		368		348
Gap Global | Europe
Segment Reporting Information [Line Items]
Net sales										626		630		726
Gap Global | Asia
Segment Reporting Information [Line Items]
Net sales										1,117		1,215		1,215
Gap Global | Other Regions
Segment Reporting Information [Line Items]
Net sales										112		129		159
Old Navy Global
Segment Reporting Information [Line Items]
Net sales										7,238		6,814		6,675
Old Navy Global | U.S.
Segment Reporting Information [Line Items]
Net sales	[1]									6,570		6,051		5,987
Old Navy Global | Canada
Segment Reporting Information [Line Items]
Net sales										547		490		467
Old Navy Global | Europe
Segment Reporting Information [Line Items]
Net sales										0		0		0
Old Navy Global | Asia
Segment Reporting Information [Line Items]
Net sales										50		220		194
Old Navy Global | Other Regions
Segment Reporting Information [Line Items]
Net sales										71		53		27
Banana Republic Global
Segment Reporting Information [Line Items]
Net sales										2,380		2,471		2,656
Banana Republic Global | U.S.
Segment Reporting Information [Line Items]
Net sales	[1]									2,017		2,052		2,211
Banana Republic Global | Canada
Segment Reporting Information [Line Items]
Net sales										225		223		229
Banana Republic Global | Europe
Segment Reporting Information [Line Items]
Net sales										15		59		71
Banana Republic Global | Asia
Segment Reporting Information [Line Items]
Net sales										96		109		112
Banana Republic Global | Other Regions
Segment Reporting Information [Line Items]
Net sales										27		28		33
Other entities
Segment Reporting Information [Line Items]
Net sales										919	[2]	776	[2]	715	[3]
Other entities | U.S.
Segment Reporting Information [Line Items]
Net sales	[1]									916	[2]	773	[2]	712	[3]
Other entities | Canada
Segment Reporting Information [Line Items]
Net sales										3	[2]	3	[2]	3	[3]
Other entities | Europe
Segment Reporting Information [Line Items]
Net sales										0	[2]	0	[2]	0	[3]
Other entities | Asia
Segment Reporting Information [Line Items]
Net sales										0	[2]	0	[2]	0	[3]
Other entities | Other Regions
Segment Reporting Information [Line Items]
Net sales										$ 0	[2]	$ 0	[2]	$ 0	[3]

[1] U.S. includes the United States, Puerto Rico, and Guam.

[2] Includes Athleta, Intermix, and, beginning in the fourth quarter of fiscal 2016, Weddington Way.

[3] Includes Athleta, Intermix, and Piperlime, which was discontinued as of the first quarter of fiscal 2015.