Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Name:	us-gaap_Goodwill
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Intangible Assets - Information by Segment (Details) - USD ($)	Jun. 30, 2022	Dec. 31, 2021
Intangible assets
Goodwill	$ 2,139,700,000	$ 2,124,100,000
Retail automotive dealership
Intangible assets
Goodwill	1,598,600,000
Retail commercial truck dealership
Intangible assets
Goodwill	465,200,000
Other
Intangible assets
Goodwill	75,900,000
Non-Automotive Investments
Intangible assets
Goodwill	$ 0