Summary of Significant Accounting Policies (Recently Adopted Accounting Pronouncements) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 28, 2018	Oct. 29, 2017	Oct. 28, 2018	Oct. 29, 2017	Jan. 29, 2018	Jan. 28, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred Revenue	$ (1,858)		$ (1,858)			$ (1,805)
Other Liabilities, Noncurrent	2,352		2,352			2,614
Revenue from Contract with Customer, Excluding Assessed Tax	26,302	$ 25,026	81,712	$ 77,021
Receivables, net	2,171		2,171			1,952
Other current assets	1,120		1,120			638
Other accrued expenses	2,685		2,685			$ 2,224
Cost of sales	17,151	16,378	53,579	50,758
Gross profit	9,151	8,648	28,133	26,263
Selling, general and administrative	4,808	$ 4,514	14,591	$ 13,424
Accounting Standards Update 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred Revenue					$ 99
Other Liabilities, Noncurrent					24
Revenue from Contract with Customer, Excluding Assessed Tax	64		130
Receivables, net	(44)		(44)
Other current assets	268		268
Other accrued expenses	224		224
Cost of sales	(83)		(300)
Gross profit	147		430
Selling, general and administrative	147		430
Accounting Standards Update 2014-09 [Member] | Calculated under Revenue Guidance in Effect before Topic 606 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	26,238		81,582
Receivables, net	2,215		2,215
Other current assets	852		852
Other accrued expenses	2,461		2,461
Cost of sales	17,234		53,879
Gross profit	9,004		27,703
Selling, general and administrative	$ 4,661		$ 14,161
Retained Earnings [Member] | Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of change on equity					$ 75