SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Summary of Significant Accounting Policies [Line Items]
Expense related to carbon offset credits	$ 116,000,000	$ 95,000,000
Derivative contracts, net	47,000,000	17,000,000
Depreciation and amortization expense related to property and equipment	2,107,000,000	1,998,000,000	$ 2,312,000,000
Amortization of capitalized software	307,000,000	301,000,000	304,000,000
Net book value of capitalized software	891,000,000	876,000,000
Fuel card obligation	1,100,000,000	1,100,000,000
Advertising expense	302,000,000	$ 198,000,000	$ 119,000,000
Fuel Card Obligation
Summary of Significant Accounting Policies [Line Items]
Purchasing card maximum limit	$ 1,100,000,000
Minimum
Summary of Significant Accounting Policies [Line Items]
Estimated residual value (percent)	5.00%
Maximum
Summary of Significant Accounting Policies [Line Items]
Estimated residual value (percent)	10.00%
Software and software development costs | Minimum
Summary of Significant Accounting Policies [Line Items]
Estimated useful life	3 years
Software and software development costs | Maximum
Summary of Significant Accounting Policies [Line Items]
Estimated useful life	15 years