Investments in Fixed Maturity Securities (HTM Allowance for Credit Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Roll Forward]
Allowance for expected credit losses, beginning of period	$ 107	$ 378	$ 114	$ 387
Cumulative effect adjustment resulting from changes in accounting principles	53	127	53	127
Provision for expected credit losses	(54)	(251)	(61)	(260)
Allowance for expected credit losses, end of period	$ 53	$ 127	$ 53	$ 127