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SCHEDULE I SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES (Details) $ in Millions | Dec. 31, 2021 USD ($)
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Summary of investments other than investments in related parties |
Cost | $ 3,784.4
Carrying Value | 4,265.3
Fair Value | 4,265.3
Fixed maturity investments |
Summary of investments other than investments in related parties |
Cost | 1,895.5
Carrying Value | 1,908.9
Fair Value | 1,908.9
U.S. Government and agency obligations |
Summary of investments other than investments in related parties |
Cost | 212.1
Carrying Value | 211.5
Fair Value | 211.5
Debt securities issued by corporations |
Summary of investments other than investments in related parties |
Cost | 993.3
Carrying Value | 992.9
Fair Value | 992.9
Municipal obligations |
Summary of investments other than investments in related parties |
Cost | 276.4
Carrying Value | 291.9
Fair Value | 291.9
Mortgage and asset-backed securities |
Summary of investments other than investments in related parties |
Cost | 277.2
Carrying Value | 277.6
Fair Value | 277.6
Collateralized loan obligations |
Summary of investments other than investments in related parties |
Cost | 136.5
Carrying Value | 135.0
Fair Value | 135.0
Short-term investments |
Summary of investments other than investments in related parties |
Cost | 465.9
Carrying Value | 465.9
Fair Value | 465.9
Investment in MediaAlpha |
Summary of investments other than investments in related parties |
Cost | 0.0
Carrying Value | 261.6
Fair Value | 261.6
Common equity securities - Industrial, Miscellaneous, and Other |
Summary of investments other than investments in related parties |
Cost | 236.3
Carrying Value | 251.1
Fair Value | 251.1
Other long-term investments |
Summary of investments other than investments in related parties |
Cost | 1,186.7
Carrying Value | 1,377.8
Fair Value | $ 1,377.8

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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 http://asc.fasb.org/extlink&oid=122147990&loc=d3e611379-123010 + Details
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