Investments (Schedule of Net Realized Investment Gains (Losses)) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Debt Securities, Available-for-Sale [Line Items]
Total impairment gains (losses):	$ 7	$ (155)
Portion of impairment losses recognized in other comprehensive income before taxes:	0	(102)
Net impairment gains (losses) recognized in earnings	7	(257)
Gross realized gains, available-for-sale fixed maturities	580	774
Gross realized (losses), available-for-sale fixed maturities	(2,999)	(2,609)
Net realized gains (losses), trading fixed maturities	8	9
Net realized gains (losses), equity investments	225	(598)
Net realized gains (losses), other investments	22	0
Change in unrealized holding gains (losses), trading fixed maturities	3	(188)
Change in unrealized holding gains (losses), equity investments	(1,261)	1,216
Change in unrealized holding gains (losses), convertible securities, carried at fair value	(10)	(40)
Net investment gains (losses)	(3,425)	(1,693)
Corporate debt
Debt Securities, Available-for-Sale [Line Items]
Total impairment gains (losses):	0	(415)
Asset-backed securities
Debt Securities, Available-for-Sale [Line Items]
Total impairment gains (losses):	$ 7	$ 260

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