Fair Value Measurements - Fair Value of Financial Instruments (Details) - USD ($) $ in Millions	May 01, 2020	Jan. 31, 2020	May 03, 2019
Financial Instruments
Long-term debt carrying value (excluding finance lease obligations)	$ 20,111	$ 16,653	$ 17,096
Unsecured Notes
Financial Instruments
Long-term debt carrying value (excluding finance lease obligations)	20,106	16,648	17,090
Mortgage Notes
Financial Instruments
Long-term debt carrying value (excluding finance lease obligations)	5	5	6
Estimate of Fair Value
Financial Instruments
Long-term debt fair value (excluding finance lease obligations)	23,214	18,814	17,267
Estimate of Fair Value | Unsecured Notes | Fair Value (Level 1)
Financial Instruments
Long-term debt fair value (excluding finance lease obligations)	23,209	18,808	17,261
Estimate of Fair Value | Mortgage Notes | Fair Value (Level 2)
Financial Instruments
Long-term debt fair value (excluding finance lease obligations)	$ 5	$ 6	$ 6