v3.25.4

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Statement of Financial Position [Abstract]
Accounts Receivable, allowance for credit losses	$ 3.3	$ 3.3
Auto loans receivable, allowance for credit losses	$ 95.4	$ 54.8
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock authorized (in shares)	1,500,000,000	1,500,000,000
Common stock issued (in shares)	63,562,149	63,562,149
Treasury Stock, Common, Shares	28,362,366	24,527,869

Amount of allowance for credit loss on accounts receivable, classified as current.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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-Name Accounting Standards Codification
-Section S99
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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Amount of allowance for credit loss on financing receivable, classified as noncurrent.

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Face amount or stated value per share of common stock.

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AUTONATION, INC. 10-K