Investments Equity Securities (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Schedule of Equity Securities and Other [Line Items]
Equity Securities, FV-NI, Cost	$ 87.1	$ 96.5
Equity Securities, FV-NI	171.5	184.0
Industrial and Miscellaneous [Member]
Schedule of Equity Securities and Other [Line Items]
Equity Securities, FV-NI, Cost	74.9	81.7
Equity Securities, FV-NI	149.1	157.9
Other [Member]
Schedule of Equity Securities and Other [Line Items]
Equity Securities, FV-NI, Cost	12.2	14.8
Equity Securities, FV-NI	$ 22.4	$ 26.1

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.

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