Investments (Credit Quality of Agricultural and Residential Mortgage Loans) (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Mortgage Loans, Gross	$ 82,904	$ 79,860
Mortgage Loans in Process of Foreclosure, Amount	145	70
Residential Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	1,482
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,274
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	380
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	1,033
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	453
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	7,086
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 11,708	11,196
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	$ 1,476
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,268
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	372
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	987
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	437
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	6,684
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 11,224
Loans Receivable Residential Mortgage Percentage	95.90%
Residential Mortgage Loans | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 6
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	6
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	8
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	46
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	16
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	402
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 484
Loans Receivable Residential Mortgage Percentage	4.10%
Agricultural Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 2,299
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,965
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	3,016
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	1,967
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	2,489
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	4,964
Financing Receivable, Revolving	1,223
Mortgage Loans, Gross	$ 18,923	$ 18,111
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	$ 2,147
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,646
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	2,644
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	1,707
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	2,389
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	4,413
Financing Receivable, Revolving	1,175
Mortgage Loans, Gross	$ 17,121
Loans Receivable Agricultural Mortgage Percentage	90.40%
Agricultural Mortgage Loans | 65% to 75%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 152
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	319
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	343
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	184
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	100
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	495
Financing Receivable, Revolving	44
Mortgage Loans, Gross	$ 1,637
Loans Receivable Agricultural Mortgage Percentage	8.70%
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	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	12
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 12
Loans Receivable Agricultural Mortgage Percentage	0.10%
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	29
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	76
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	44
Financing Receivable, Revolving	4
Mortgage Loans, Gross	$ 153
Loans Receivable Agricultural Mortgage Percentage	0.80%