Investments (Mortgage Loans by Portfolio Segment) (Details) - Mortgage Loans - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit losses	$ 22,996	$ 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	$ (119)	$ (123)
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	$ 22,877	$ 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	$ 13,547	$ 12,159
Financing receivable, before allowance for credit losses as a percentage of financing receivable, net of allowance for credit losses	59.20%	61.40%
Financing receivable, allowance for credit losses	$ (49)	$ (67)
Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit losses	$ 4,333	$ 4,128
Financing receivable, before allowance for credit losses as a percentage of financing receivable, net of allowance for credit losses	18.90%	20.90%
Financing receivable, allowance for credit losses	$ (15)	$ (12)
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit losses	$ 5,116	$ 3,623
Financing receivable, before allowance for credit losses as a percentage of financing receivable, net of allowance for credit losses	22.40%	18.30%
Financing receivable, allowance for credit losses	$ (55)	$ (44)