Investments Equity Securities (Details) - USD ($) $ in Millions |
Jun. 30, 2024 |
Dec. 31, 2023 |
---|---|---|
Schedule of Equity Securities and Other [Line Items] | ||
Equity Securities, FV-NI, Cost | $ 134.4 | $ 125.9 |
Equity Securities, FV-NI | 232.6 | 211.2 |
Industrial and Miscellaneous [Member] | ||
Schedule of Equity Securities and Other [Line Items] | ||
Equity Securities, FV-NI, Cost | 111.5 | 104.4 |
Equity Securities, FV-NI | 202.5 | 181.7 |
Other [Member] | ||
Schedule of Equity Securities and Other [Line Items] | ||
Equity Securities, FV-NI, Cost | 22.9 | 21.5 |
Equity Securities, FV-NI | $ 30.1 | $ 29.5 |