Investments, Securities with Continuous Unrealized Loss Position (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) Securities	Dec. 31, 2023 USD ($) Securities
Available-for-sale securities, continuous unrealized loss position, Fair Value [Abstract]
Less than 12 months	$ 159,874	$ 6,878
12 months or longer	33,773	183,695
Total	193,647	190,573
Available-for-sale securities, continuous unrealized loss position, Unrealized Losses [Abstract]
Less than 12 months	20,326	53
12 months or longer	8,464	21,638
Total	$ 28,790	$ 21,691
Number of securities in unrealized loss position | Securities	237	311
Allowance for expected credit losses on available-for-sale fixed maturities	$ 0	$ 0
Temporary impairments	0
U.S. Treasury Securities and Obligations of U.S. Government Agencies and Authorities [Member]
Available-for-sale securities, continuous unrealized loss position, Fair Value [Abstract]
Less than 12 months	23,763	5,194
12 months or longer	19,259	39,476
Total	43,022	44,670
Available-for-sale securities, continuous unrealized loss position, Unrealized Losses [Abstract]
Less than 12 months	2,410	37
12 months or longer	3,516	4,907
Total	5,926	4,944
Allowance for expected credit losses on available-for-sale fixed maturities		0
Obligations of States and Political Subdivisions [Member]
Available-for-sale securities, continuous unrealized loss position, Fair Value [Abstract]
Less than 12 months	8,183	1,145
12 months or longer	0	5,936
Total	8,183	7,081
Available-for-sale securities, continuous unrealized loss position, Unrealized Losses [Abstract]
Less than 12 months	1,702	3
12 months or longer	0	1,421
Total	1,702	1,424
Allowance for expected credit losses on available-for-sale fixed maturities		0
Corporate Securities [Member]
Available-for-sale securities, continuous unrealized loss position, Fair Value [Abstract]
Less than 12 months	127,928	539
12 months or longer	14,514	138,283
Total	142,442	138,822
Available-for-sale securities, continuous unrealized loss position, Unrealized Losses [Abstract]
Less than 12 months	16,214	13
12 months or longer	4,948	15,310
Total	$ 21,162	15,323
Allowance for expected credit losses on available-for-sale fixed maturities		$ 0