Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

No definition available.

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- Definition

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

+ References

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)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

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- Definition

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 718
-SubTopic 10
-Section 25
-Paragraph 19A
-URI http://asc.fasb.org/extlink&oid=96949009&loc=SL79513924-113897

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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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
-URI http://asc.fasb.org/extlink&oid=6486086&loc=d3e24387-158525

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- References

No definition available.

+ Details

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- Definition

Number of Advertisers

+ References

No definition available.

+ Details

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- Definition

Number of Publishers

+ References

No definition available.

+ Details

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- Definition

Percentage of par value of policy reinsured.

+ References

No definition available.

+ Details

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Basis of Presentation and Significant Accouting Policies (Basis of Presentation) (Details) $ / shares in Units, $ in Millions	6 Months Ended
	Jun. 30, 2018 USD ($) advertiser publisher	Jun. 30, 2017 USD ($)	May 11, 2018	Dec. 31, 2017	Sep. 28, 2017 $ / shares	Jul. 31, 2012 USD ($)
HG Global
Basis of Presentation
Percentage of par value of policy reinsured	15.00%
Surplus notes	$ 499.0					$ 503.0
MediaAlpha
Basis of Presentation
Ownership interest (as a percent)	62.30%			64.40%
Number of advertisers \| advertiser	580
Number of publishers \| publisher	325
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	$ 8.4	$ 9.2
OneBeacon
Basis of Presentation
Business acquisition, share price \| $ / shares					$ 18.10
NSM Insurance HoldCo, LLC
Basis of Presentation
Ownership interest (as a percent)			95.00%