Revenue Recognition - Summary of Revenue from Contracts with Customers by Services and Products (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Disaggregation of Revenue [Line Items]
Revenue	$ 231,358	$ 219,419	$ 665,846	$ 691,119
Marketplace
Disaggregation of Revenue [Line Items]
Revenue	204,019	177,909	586,405	515,986
Dealer-to-Dealer
Disaggregation of Revenue [Line Items]
Revenue	13,876	23,290	47,867	84,945
Sell My Car - Instant Max Cash Offer
Disaggregation of Revenue [Line Items]
Revenue	$ 13,463	$ 18,220	$ 31,574	$ 90,188

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.

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+ Details