LONG-TERM DEBT - ABL Credit Facility (Details) - USD ($) $ in Millions	Jan. 29, 2022	Jul. 31, 2021	Oct. 19, 2018
Debt Instrument [Line Items]
Line of credit facility, current borrowing capacity	$ 2,096
Notes payable	2,309	$ 2,175
Debt issuance costs, net	28	$ 35
Letter of credit
Debt Instrument [Line Items]
Line of credit facility, current borrowing capacity	115
Line of credit | Revolving credit facility | ABL Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 2,100
Line of credit facility, maximum borrowing capacity, optional increase			$ 600
Remaining availability under ABL credit facility	991
Line of credit | Revolving credit facility | ABL Credit Facility | Accounts receivable
Debt Instrument [Line Items]
Line of credit facility, borrowing base, eligibility percent			90.00%
Line of credit | Revolving credit facility | ABL Credit Facility | Credit card receivable
Debt Instrument [Line Items]
Line of credit facility, borrowing base, eligibility percent			90.00%
Line of credit | Revolving credit facility | ABL Credit Facility | Inventories
Debt Instrument [Line Items]
Line of credit facility, borrowing base, eligibility percent			90.00%
Line of credit | Revolving credit facility | ABL Credit Facility | Pharmacy receivable
Debt Instrument [Line Items]
Line of credit facility, borrowing base, eligibility percent			90.00%
Line of credit | Revolving credit facility | ABL Credit Facility | United States
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	2,050		$ 2,050
Line of credit facility, borrowing capacity, reserves	178
Line of credit facility, current borrowing capacity	2,439
Notes payable	990
Debt issuance costs, net	6
Letters of credit outstanding, amount	115
Line of credit | Revolving credit facility | ABL Credit Facility | Canada
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	50		50
Line of credit facility, borrowing capacity, reserves	5
Line of credit facility, current borrowing capacity	46
Remaining availability under ABL credit facility	2,096
Notes payable	0
Letters of credit outstanding, amount	$ 0
Line of credit | Letter of credit | ABL Credit Facility | United States
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			300
Line of credit | Letter of credit | ABL Credit Facility | Canada
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 25