Business Combination - Schedule of Allocation of Purchase Consideration to Tangible and Intangible Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Assets acquired
Goodwill	$ 73,058	$ 74,116
Boston-based Dataxu, Inc, Demand-Side Platform (DSP)
Assets acquired
Current assets	50,829
Restricted cash	1,303
Property and equipment, net	4,503
Goodwill	71,676
Operating lease right-of-use assets	24,658
Other long-term assets	235
Total assets acquired	223,404
Liabilities assumed
Current liabilities	(51,428)
Operating lease liabilities	(24,658)
Total liabilities assumed	(76,086)
Total purchase consideration	147,318
Boston-based Dataxu, Inc, Demand-Side Platform (DSP) \| Developed Technology
Assets acquired
Intangible assets	$ 56,400
Liabilities assumed
Estimated Useful Lives (in years)	6 years
Boston-based Dataxu, Inc, Demand-Side Platform (DSP) \| Customer Relationships
Assets acquired
Intangible assets	$ 13,400
Liabilities assumed
Estimated Useful Lives (in years)	4 years
Boston-based Dataxu, Inc, Demand-Side Platform (DSP) \| Tradename
Assets acquired
Intangible assets	$ 400
Liabilities assumed
Estimated Useful Lives (in years)	6 months

Acquired finite-lived intangible assets, estimated useful life.

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Business combination recognized identifiable assets acquired and liabilities assumed operating lease liabilities.

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Business combination recognized identifiable assets acquired and liabilities assumed operating lease right-of-use assets.

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Business combination recognized identifiable assets acquired and liabilities assumed restricted cash.

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Amount of assets acquired at the acquisition date.

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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