Revenue Information - Schedule of Revenue Categories (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenue Information
Revenue	$ 65,766	$ 58,554	$ 130,871	$ 137,471
Dealer revenue
Revenue Information
Revenue	62,670	50,049	124,727	123,847
OEM incentives revenue
Revenue Information
Revenue	2,768	4,771	5,565	8,294
Other revenue
Revenue Information
Revenue	$ 328	$ 3,734	$ 579	$ 5,330

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details