Business Combination - Acquisition Purchase Price Allocation (Parenthetical) (Details) $ in Thousands	Feb. 21, 2018 USD ($)
Business Acquisition [Line Items]
DI Acquisition-Date Fair Value	$ 71,900
Acquired Software
Business Acquisition [Line Items]
DI Acquisition-Date Fair Value	$ 39,500
Weighted-Average Amortization Period (in years)	4 years
Customer Relationships
Business Acquisition [Line Items]
DI Acquisition-Date Fair Value	$ 18,300
Weighted-Average Amortization Period (in years)	4 years
Trade Names
Business Acquisition [Line Items]
DI Acquisition-Date Fair Value	$ 14,100
Weighted-Average Amortization Period (in years)	10 years
Dealer Inspire ("DI") and Launch Digital Marketing ("LDM")
Business Acquisition [Line Items]
Cash consideration	$ 164,333
Less: Cash settlement of DI Acquisition's unvested equity awards	(5,700)
Less: Cash acquired	(1,480)
Payment for DI Acquisition, net	157,153
Additional cash consideration required to be paid to former owners of acquired business	$ 15,000
Revenue targets for contingent consideration performance period	3 years
DI Acquisition-Date Fair Value	$ 71,900
Dealer Inspire ("DI") and Launch Digital Marketing ("LDM") \| Product and Technology
Business Acquisition [Line Items]
Less: Cash settlement of DI Acquisition's unvested equity awards	3,900
Dealer Inspire ("DI") and Launch Digital Marketing ("LDM") \| Cost of Revenue and Operations
Business Acquisition [Line Items]
Less: Cash settlement of DI Acquisition's unvested equity awards	1,000
Dealer Inspire ("DI") and Launch Digital Marketing ("LDM") \| Selling and Marketing Expense
Business Acquisition [Line Items]
Less: Cash settlement of DI Acquisition's unvested equity awards	500
Dealer Inspire ("DI") and Launch Digital Marketing ("LDM") \| General and Administrative Expense
Business Acquisition [Line Items]
Less: Cash settlement of DI Acquisition's unvested equity awards	$ 300

Cash settlement of acquisition unvested equity awards.

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The maximum amount of contingent consideration that may be paid to the former owners of the acquisition.

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Revenue targets for contingent consideration performance period.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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