Investments (Credit Losses Related to Debt Securities) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss beginning balance	$ 2,774	$ 1,602	$ 3,399	$ 555
No allowance for credit losses has been previously recognized	1,263	1,804	1,416	2,544
An allowance for credit losses was recorded in a previous period			1,727	470
Securities sold during the period	(6)	(3)	(2,511)	(166)
Allowance for credit loss ending balance	4,031	3,403	4,031	3,403
Corporate Debt
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss beginning balance	2,250	1,210	2,608	0
No allowance for credit losses has been previously recognized	1,263	1,398	1,263	2,138
An allowance for credit losses was recorded in a previous period			1,727	470
Securities sold during the period	0	0	(2,085)	0
Allowance for credit loss ending balance	3,513	2,608	3,513	2,608
Residential mortgage-backed securities
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss beginning balance	188	203	197	211
No allowance for credit losses has been previously recognized	0	0	0	0
An allowance for credit losses was recorded in a previous period			0	0
Securities sold during the period	(3)	(2)	(12)	(10)
Allowance for credit loss ending balance	185	201	185	201
Other commercial mortgage-backed securities
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss beginning balance	62	0	406	151
No allowance for credit losses has been previously recognized	0	406	62	406
An allowance for credit losses was recorded in a previous period			0	0
Securities sold during the period	0	0	(406)	(151)
Allowance for credit loss ending balance	62	406	62	406
Other asset-backed securities
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss beginning balance	274	189	188	193
No allowance for credit losses has been previously recognized	0	0	91	0
An allowance for credit losses was recorded in a previous period			0	0
Securities sold during the period	(3)	(1)	(8)	(5)
Allowance for credit loss ending balance	$ 271	$ 188	$ 271	$ 188