Investments (Rollforward of the Allowance for Credit Losses for Mortgage Loans by Portfolio Segment) (Details) - Mortgage Loans - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing receivable, allowance for credit losses, beginning of period	$ 119	$ 123
Current period provision	23	(1)
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery	(5)	(23)
Financing receivable, allowance for credit losses, end of period	137	99
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing receivable, allowance for credit losses, beginning of period	49	67
Current period provision	22	1
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery	(4)	(23)
Financing receivable, allowance for credit losses, end of period	67	45
Agricultural
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing receivable, allowance for credit losses, beginning of period	15	12
Current period provision	1	3
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery	(1)	0
Financing receivable, allowance for credit losses, end of period	15	15
Residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing receivable, allowance for credit losses, beginning of period	55	44
Current period provision	0	(5)
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery	0	0
Financing receivable, allowance for credit losses, end of period	$ 55	$ 39