The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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- Definition

Financial instruments issued by insurance entities (surplus notes) that are includable in surplus for statutory accounting purposes as prescribed or permitted by state laws and regulations that are liabilities of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 470
-Section 45
-Paragraph 1
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- Definition

Number of Advertisers

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Number of Publishers

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- Definition

Percentage of par value of policy reinsured.

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Summary of Significant Accounting Policies (Basis of Presentation) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2017 USD ($) publisher advertiser	Jun. 30, 2016 USD ($)	Dec. 31, 2016	Jul. 31, 2012 USD ($)
HG Global
Basis of Presentation
Percentage of par value of policy reinsured	15.00%
Surplus notes				$ 503.0
MediaAlpha
Basis of Presentation
Number of advertisers \| advertiser	300
Number of publishers \| publisher	225
Preferred Stock \| HG Global
Basis of Presentation
Ownership interest (as a percent)	96.90%		96.90%
Common Stock \| HG Global
Basis of Presentation
Ownership interest (as a percent)	88.40%		88.40%
Restricted Stock
Basis of Presentation
Payments Related to Tax Withholding for Share-based Compensation	$ 9.2	$ 5.8