Investments (Allowance for Credit Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of year	$ 37,715	$ 37,689
Addition to (release of) allowance for expected losses	2,069	4,993
Total ending balance	39,784	42,682
Commercial mortgage loans
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of year	33,004	36,758
Addition to (release of) allowance for expected losses	1,766	5,011
Total ending balance	34,770	41,769
Agricultural Property Loans
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of year	4,711	931
Addition to (release of) allowance for expected losses	303	(18)
Total ending balance	$ 5,014	$ 913