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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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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

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- Definition

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Goodwill and Intangible Assets

+ References

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- Definition

Equity Method Investment, Fully Diluted Ownership Percentage

+ References

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Goodwill and Other Intangible Assets - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2019	Feb. 26, 2019	Dec. 31, 2018	May 18, 2018	May 11, 2018
NSM Insurance HoldCo, LLC
Goodwill [Line Items]
Goodwill and intangible assets acquired					$ 383.0
Ownership interest (as a percent)	95.30%		95.50%		95.00%
Fully diluted ownership interest (as a percent)	84.80%		85.00%
Fresh Insurance Services Group Limited
Goodwill [Line Items]
Goodwill and intangible assets acquired				$ 54.6
Ownership interest (as a percent)				100.00%
MediaAlpha
Goodwill [Line Items]
Ownership interest (as a percent)		48.30%
Fully diluted ownership interest (as a percent)		42.00%