Revenue Recognition - Summary of Revenue from Contracts with Customers by Services and Products (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Revenue	$ 914,242	$ 1,655,035	$ 951,373
Marketplace
Disaggregation of Revenue [Line Items]
Revenue	698,236	658,771	636,942
Dealer-to-Dealer
Disaggregation of Revenue [Line Items]
Revenue	109,802	320,119	224,831
Instant Max Cash Offer
Disaggregation of Revenue [Line Items]
Revenue	$ 106,204	$ 676,145	$ 89,600

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 924
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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+ Details