FAIR VALUE MEASUREMENTS OF FINANCIAL INSTRUMENTS - Recurring Fair Value Measurements (Details) - USD ($) $ in Millions	Jan. 28, 2023	Jul. 30, 2022
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Asset, Current, Statement of Financial Position [Extensible Enumeration]	Prepaid expenses and other current assets	Prepaid expenses and other current assets
Derivative Asset, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other long-term assets	Other long-term assets
Derivative Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued expenses and other current liabilities
Derivative Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]		Other long-term liabilities
Fair value, measurements, recurring \| Level 1 \| Fuel derivatives \| Designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Current derivative assets		$ 0
Current derivative liability	$ 0
Fair value, measurements, recurring \| Level 1 \| Interest rate swaps \| Designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Current derivative assets	0	0
Noncurrent derivative assets	0	0
Noncurrent derivative liability		0
Fair value, measurements, recurring \| Level 2 \| Fuel derivatives \| Designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Current derivative assets		3
Current derivative liability	1
Fair value, measurements, recurring \| Level 2 \| Interest rate swaps \| Designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Current derivative assets	17	3
Noncurrent derivative assets	5	1
Noncurrent derivative liability		2
Fair value, measurements, recurring \| Level 3 \| Fuel derivatives \| Designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Current derivative assets		0
Current derivative liability	0
Fair value, measurements, recurring \| Level 3 \| Interest rate swaps \| Designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Current derivative assets	0	0
Noncurrent derivative assets	$ 0	0
Noncurrent derivative liability		$ 0

Indicates line item in statement of financial position that includes derivative asset classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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