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Equity-Method Eligible Investments - Carrying Values of Equity Method Eligible Investments Recorded within Other Long-Term Investments (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Investments in unconsolidated affiliates
Other long-term investments	$ 1,032.2	$ 786.8
Marketing Technology (MediaAlpha)
Investments in unconsolidated affiliates
Other long-term investments	600.2	802.2
Equity Method Investments
Investments in unconsolidated affiliates
Other long-term investments	$ 706.2	$ 698.1

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- Definition

Amount of long-term investments classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(f))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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+ References

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