Business Combination - Additional Information (Details) - Boston-based Dataxu, Inc, Demand-Side Platform (DSP) - USD ($) shares in Thousands, $ in Millions		2 Months Ended
Nov. 08, 2019	Dec. 31, 2019
Business Acquisition [Line Items]
Business combination, date of merger agreement	Oct. 22, 2019
Purchase consideration	$ 148.4
Business combination, aggregate cash consideration	78.7
Business combination, aggregate fair value	69.7
Amount deposited to escrow account	18.8
Purchase consideration included in escrow deposit	17.5
Business combination, contingent consideration	$ 1.8
Business combination, pro forma information, revenue		$ 16.8
Business combination, pro forma information, cost of revenue		10.2
Business combination, pro forma information, gross profit		$ 6.6
Maximum
Business Acquisition [Line Items]
Measurement period	1 year
Identifiable intangible assets, estimated useful lives	6 years
Minimum
Business Acquisition [Line Items]
Identifiable intangible assets, estimated useful lives	6 months
General and Administrative Expenses
Business Acquisition [Line Items]
Acquisition related cost	$ 3.9
Common Stock
Business Acquisition [Line Items]
Shares of common stock issued	571,459

Business combination pro forma information cost of revenue of acquiree since acquisition date actual.

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Escrow deposit disbursements related to acquisition.

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Escrow deposit disbursements related to acquisition purchase consideration.

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Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

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Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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