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SCHEDULE I SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES (Details) $ in Millions | Dec. 31, 2022 USD ($)
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Summary of investments other than investments in related parties |
Cost | $ 5,002.6
Carrying Value | 5,170.0
Fair Value | 5,170.0
Fixed maturity investments |
Summary of investments other than investments in related parties |
Cost | 2,076.0
Carrying Value | 1,920.9
Fair Value | 1,920.9
U.S. Government and agency obligations |
Summary of investments other than investments in related parties |
Cost | 216.6
Carrying Value | 206.4
Fair Value | 206.4
Debt securities issued by corporations |
Summary of investments other than investments in related parties |
Cost | 1,098.3
Carrying Value | 1,018.8
Fair Value | 1,018.8
Municipal obligations |
Summary of investments other than investments in related parties |
Cost | 281.6
Carrying Value | 258.6
Fair Value | 258.6
Mortgage and asset-backed securities |
Summary of investments other than investments in related parties |
Cost | 288.7
Carrying Value | 254.2
Fair Value | 254.2
Collateralized loan obligations |
Summary of investments other than investments in related parties |
Cost | 190.8
Carrying Value | 182.9
Fair Value | 182.9
Short-term investments |
Summary of investments other than investments in related parties |
Cost | 925.2
Carrying Value | 924.1
Fair Value | 924.1
Investment in MediaAlpha |
Summary of investments other than investments in related parties |
Cost | 0.0
Carrying Value | 168.6
Fair Value | 168.6
Common equity securities - Industrial, Miscellaneous, and Other |
Summary of investments other than investments in related parties |
Cost | 324.3
Carrying Value | 334.6
Fair Value | 334.6
Exchange traded funds |
Summary of investments other than investments in related parties |
Cost | 336.3
Carrying Value | 333.8
Fair Value | 333.8
Total common equity securities |
Summary of investments other than investments in related parties |
Cost | 660.6
Carrying Value | 668.4
Fair Value | 668.4
Other long-term investments |
Summary of investments other than investments in related parties |
Cost | 1,340.8
Carrying Value | 1,488.0
Fair Value | $ 1,488.0

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- Definition Amount of investment held by insurance company, excluding investment in related party. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 7 -Subparagraph (SX 210.12-15(Column D)) -URI https://asc.fasb.org/extlink&oid=122147990&loc=d3e611379-123010 + Details
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