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, 2024	Sep. 30, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing receivable, allowance for credit losses, beginning of period	$ 137	$ 119
Current period provision	43	23
Charge-offs, net of recoveries	(13)	(5)
Financing receivable, allowance for credit losses, end of period	167	137
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing receivable, allowance for credit losses, beginning of period	69	49
Current period provision	39	22
Charge-offs, net of recoveries	(13)	(4)
Financing receivable, allowance for credit losses, end of period	95	67
Agricultural
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing receivable, allowance for credit losses, beginning of period	19	15
Current period provision	11	1
Charge-offs, net of recoveries	0	(1)
Financing receivable, allowance for credit losses, end of period	30	15
Residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing receivable, allowance for credit losses, beginning of period	49	55
Current period provision	(7)	0
Charge-offs, net of recoveries	0	0
Financing receivable, allowance for credit losses, end of period	$ 42	$ 55