Subsequent Event	12 Months Ended
Dec. 31, 2021
Subsequent Events [Abstract]
Subsequent Event	Note 16. Subsequent Events Accu-Trade Acquisition. In February 2022, the Company signed an agreement to acquire 100% of the assets of Accu-Trade, Galves Market Data and MADE Logistics ("Accu-Trade"), which includes real-time, VIN-specific appraisal and valuation data, instant guaranteed offer capabilities, and logistics technology. Consideration for the transaction will be $65 million in cash at closing. There is also the potential for additional cash and stock consideration based on achievement of certain financial thresholds. The transaction is expected to close in March 2022. Share Repurchase Program. In February 2022, the Company’s Board of Directors authorized a three-year share repurchase program to acquire up to $200 million of the Company’s common stock.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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