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Amount of consideration transferred in asset acquisition. Includes, but is not limited to, cash, liability incurred by acquirer, and equity interest issued by acquirer.

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Acquisitions - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Asset acquisition, consideration transferred	$ 23	$ 28
Goodwill	1,108	1,137	$ 1,101
Assets Acquisition 2019
Business Acquisition [Line Items]
Asset acquisition, consideration transferred			$ 55
Acquired finite-lived intangible assets, weighted average useful life			3 years
Payments to acquire businesses			$ 74
Goodwill			21
Fleet
Business Acquisition [Line Items]
Property acquired	22	22
Fleet \| Assets Acquisition 2019
Business Acquisition [Line Items]
Property acquired			27
Franchise Rights
Business Acquisition [Line Items]
Finite-lived intangible assets acquired	$ 28	$ 28
Acquired finite-lived intangible assets, weighted average useful life	1 year	2 years
License agreements \| Assets Acquisition 2019
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			24
Other \| Assets Acquisition 2019
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			$ 7