Investments - Financing Receivable, Interest Income on Non-Accrual Receivables (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Financing receivables, non-accrual and aging disclosures
Financing receivables, Nonaccrual, Interest Income	$ 0.2	$ 1.0	$ 0.8	$ 1.1
Commercial mortgage loans
Financing receivables, non-accrual and aging disclosures
Financing receivables, Nonaccrual, Interest Income		0.8	0.5	0.8
Residential mortgage loans
Financing receivables, non-accrual and aging disclosures
Financing receivables, Nonaccrual, Interest Income	$ 0.2	$ 0.2	$ 0.3	$ 0.3

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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+ Details