Revenue Recognition - Summary of Revenue from Contracts with Customers by Product (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Disaggregation of Revenue [Line Items]
Revenue	$ 231,963	$ 430,608
Marketplace
Disaggregation of Revenue [Line Items]
Revenue	167,127	163,289
Dealer-to-Dealer
Disaggregation of Revenue [Line Items]
Revenue	28,705	105,491
Instant Max Cash Offer
Disaggregation of Revenue [Line Items]
Revenue	$ 36,131	$ 161,828

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