Certain Long-Duration Contracts With Guarantees (Separate Account Investment Options) (Details) - Annuity Contracts - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Separate Account Investment [Line Items]
Separate Account Investment Options	$ 120,211,053	$ 121,141,825
Equity funds
Fair Value, Separate Account Investment [Line Items]
Separate Account Investment Options	69,299,203	68,436,773
Bond funds
Fair Value, Separate Account Investment [Line Items]
Separate Account Investment Options	47,895,089	51,126,536
Money market funds
Fair Value, Separate Account Investment [Line Items]
Separate Account Investment Options	$ 3,016,761	$ 1,578,516