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Acquisitions (Narrative) (Details) $ in Millions		3 Months Ended		9 Months Ended
Acquisitions (Narrative) (Details) $ in Millions	Dec. 07, 2022 USD ($)	Sep. 30, 2023 USD ($) state	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) state	Sep. 30, 2022 USD ($)	Nov. 30, 2022 USD ($)
Business Acquisition [Line Items]
Amortization expense		$ 66	$ 53	$ 210	$ 170
6 percent Senior Secured Notes due 2029 \| Senior notes
Business Acquisition [Line Items]
Debt instrument, face amount						$ 1,500
Stated interest rate		6.00%		6.00%		6.00%
Ahern Rentals
Business Acquisition [Line Items]
Number of states \| state		30		30
Aggregate consideration paid	$ 1,988
Amortization expense				$ 7