Investments (Mortgage Loans by Portfolio Segment) (Details) - Mortgage Loans - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit losses	$ 21,552	$ 19,910
Financing receivable, before allowance for credit losses as a percentage of financing receivable, net of allowance for credit losses	100.50%	100.60%
Financing receivable, allowance for credit losses	$ (103)	$ (123)	$ (96)	$ (94)
Financing receivable, allowance for credit losses as a percentage of financing receivable, net of allowance for credit losses	(0.50%)	(0.60%)
Financing receivable, net of allowance for credit losses	$ 21,449	$ 19,787
Financing receivable, after allowance for credit losses as a percentage of financing receivable, net of allowance for credit losses	100.00%	100.00%
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit losses	$ 13,020	$ 12,159
Financing receivable, before allowance for credit losses as a percentage of financing receivable, net of allowance for credit losses	60.70%	61.40%
Financing receivable, allowance for credit losses	$ (44)	$ (67)	(46)	(44)
Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit losses	$ 4,111	$ 4,128
Financing receivable, before allowance for credit losses as a percentage of financing receivable, net of allowance for credit losses	19.20%	20.90%
Financing receivable, allowance for credit losses	$ (15)	$ (12)	(13)	(15)
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit losses	$ 4,421	$ 3,623
Financing receivable, before allowance for credit losses as a percentage of financing receivable, net of allowance for credit losses	20.60%	18.30%
Financing receivable, allowance for credit losses	$ (44)	$ (44)	$ (37)	$ (35)