Investments - Allowance for Credit Losses on Available-for-sale Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, beginning of year	$ 249	$ 21
Provision and recoveries	670	500
Sales/collections and write-offs	(322)	(272)
Allowance for credit losses, end of year	$ 597	$ 249