Fair Value, Financial Assets and Liabilities Not Measured at Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Carrying Amount
Assets [Abstract]
Other invested assets, primarily mortgage loans	$ 973	$ 1,068
Liabilities [Abstract]
Short term debt	93	35
Long term debt	8,981	10,042
Estimated Fair Value
Assets [Abstract]
Other invested assets, primarily mortgage loans	1,018	1,151
Liabilities [Abstract]
Short term debt	93	36
Long term debt	9,781	11,247
Estimated Fair Value | Level 1
Assets [Abstract]
Other invested assets, primarily mortgage loans
Liabilities [Abstract]
Short term debt
Long term debt
Estimated Fair Value | Level 2
Assets [Abstract]
Other invested assets, primarily mortgage loans
Liabilities [Abstract]
Short term debt		19
Long term debt	9,170	10,482
Estimated Fair Value | Level 3
Assets [Abstract]
Other invested assets, primarily mortgage loans	1,018	1,151
Liabilities [Abstract]
Short term debt	93	17
Long term debt	$ 611	$ 765