Fair Value - Financial Assets and Liabilities Not Measured at Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Carrying Amount
Assets:
Other invested assets, primarily mortgage loans	$ 949	$ 973
Liabilities:
Short term debt	838	93
Long term debt	8,438	8,981
Estimated Fair Value
Assets:
Other invested assets, primarily mortgage loans	915	1,018
Liabilities:
Short term debt	836	93
Long term debt	8,117	9,781
Estimated Fair Value | Level 1
Assets:
Other invested assets, primarily mortgage loans
Liabilities:
Short term debt
Long term debt
Estimated Fair Value | Level 2
Assets:
Other invested assets, primarily mortgage loans
Liabilities:
Short term debt	797
Long term debt	7,472	9,170
Estimated Fair Value | Level 3
Assets:
Other invested assets, primarily mortgage loans	915	1,018
Liabilities:
Short term debt	39	93
Long term debt	$ 645	$ 611