Investments (Credit Quality of Agricultural and Residential Mortgage Loans) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Mortgage Loans, Gross	$ 91,262	$ 93,227
Mortgage Loans in Process of Foreclosure, Amount	136	140
Residential Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	807
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	961
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	2,568
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	1,771
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	341
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	7,396
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 13,844	13,096
Loans Receivable Residential Mortgage Percentage	100.00%
Residential Mortgage Loans | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 805
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	927
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	2,493
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	1,747
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	326
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	7,112
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 13,410
Loans Receivable Residential Mortgage Percentage	96.90%
Residential Mortgage Loans | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 2
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	34
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	75
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	24
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	15
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	284
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 434
Loans Receivable Residential Mortgage Percentage	3.10%
Agricultural Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 468
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,233
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	2,860
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	2,922
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	2,790
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	7,648
Financing Receivable, Revolving	1,548
Mortgage Loans, Gross	$ 19,469	$ 19,805
Loans Receivable Agricultural Mortgage Percentage	100.00%
Agricultural Mortgage Loans | Less than 65%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 459
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,177
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	2,792
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	2,602
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	2,639
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	7,090
Financing Receivable, Revolving	1,427
Mortgage Loans, Gross	$ 18,186
Loans Receivable Agricultural Mortgage Percentage	93.40%
Agricultural Mortgage Loans | 65% to 75%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 9
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	56
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	44
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	306
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	119
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	512
Financing Receivable, Revolving	104
Mortgage Loans, Gross	$ 1,150
Loans Receivable Agricultural Mortgage Percentage	5.90%
Agricultural Mortgage Loans | 76% to 80%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	24
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	3
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, Revolving	3
Mortgage Loans, Gross	$ 30
Loans Receivable Agricultural Mortgage Percentage	0.20%
Agricultural Mortgage Loans | Greater than 80%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	14
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	29
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	46
Financing Receivable, Revolving	14
Mortgage Loans, Gross	$ 103
Loans Receivable Agricultural Mortgage Percentage	0.50%