Investments (Allowance for Credit Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of year	$ 4,552	$ 1,768	$ 2,065
Cumulative effect of adoption of ASU 2016-13		2,487
Addition to (release of) allowance for expected losses	1,399	297	(297)
Total ending balance	5,951	4,552	1,768
Commercial mortgage loans
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of year	4,546	1,743	2,026
Cumulative effect of adoption of ASU 2016-13		2,495
Addition to (release of) allowance for expected losses	1,301	308	(283)
Total ending balance	5,847	4,546	1,743
Agricultural Property Loans
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of year	6	25	39
Cumulative effect of adoption of ASU 2016-13		(8)
Addition to (release of) allowance for expected losses	98	(11)	(14)
Total ending balance	$ 104	$ 6	$ 25