Business Combination - Schedule of Unaudited Pro Forma Financial Information (Details) - Boston-based Dataxu, Inc, Demand-Side Platform (DSP) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Total Revenues	$ 1,218,403	$ 884,286
Pretax loss	(87,654)	(39,919)
Net loss	$ (86,791)	$ (39,670)

Business acquisitions, pro forma pretax loss.

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- Definition

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.

+ References

No definition available.

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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