Investments (Accrued Investment Income) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Net Investment Income
Accrued investment income	$ 110,380	$ 121,604
Fixed maturities
Net Investment Income
Accrued investment income	104,552	116,342
Equity Securities
Net Investment Income
Accrued investment income	1	1
Commercial mortgage and other loans
Net Investment Income
Accrued investment income	5,484	4,828
Policy loans
Net Investment Income
Accrued investment income	12	11
Short-term investments and cash equivalents
Net Investment Income
Accrued investment income	81	158
Other
Net Investment Income
Accrued investment income	$ 250	$ 264