ACQUISITIONS AND DISPOSITIONS (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) dealership franchise
Acquisitions and Dispositions
Aggregate consideration paid for dealerships \| $	$ 49.9
Number of franchises disposed	1
U.S.
Acquisitions and Dispositions
Number of dealerships acquired \| dealership	2
Number of franchises acquired	2
Number of dealerships disposed \| dealership	1
Number of franchises disposed	1
Net pre-tax gain (loss) on dealership dispositions \| $	$ 1.0
United Kingdom
Acquisitions and Dispositions
Number of dealerships disposed \| dealership	1
Number of franchises disposed	1
Net pre-tax gain (loss) on dealership dispositions \| $	$ 0.6

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477

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