Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Amortized cost of fixed maturities	$ 7,295.0	$ 7,565.8
Allowance for credit loss, available for sale	10.7	8.2
Cost of equity securities	197.1	209.3
Premium Receivable, Allowance for Credit Loss	2.9	13.9
Allowance for credit losses	$ (10.7)	$ (8.2)
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares outstanding (in shares)	63,840,442	64,111,555
Variable Interest Entity, Primary Beneficiary
Amortized cost of fixed maturities	$ 1.7	$ 1.7
Allowance for credit loss, available for sale	0.0	0.0
Premium Receivable, Allowance for Credit Loss	0.0	0.0
Allowance for credit losses	0.0	0.0
Consolidated Entity, Excluding VIE
Amortized cost of fixed maturities	7,295.0	7,565.8
Allowance for credit loss, available for sale	10.7	8.2
Allowance for credit losses	$ (10.7)	$ (8.2)