Investments (Credit Quality of Agricultural and Residential Mortgage Loans) (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Mortgage Loans, Gross	$ 88,889	$ 89,812
Mortgage Loans in Process of Foreclosure, Amount	161	140
Residential Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	61
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,120
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	935
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	2,463
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,812
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	7,392
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 14,783	14,189
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	$ 61
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,093
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	891
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	2,371
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,778
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	7,089
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 14,283
Loans Receivable Residential Mortgage Percentage	96.60%
Residential Mortgage Loans | Nonperforming
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	27
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	44
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	92
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	34
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	303
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 500
Loans Receivable Residential Mortgage Percentage	3.40%
Agricultural Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 264
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	770
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,274
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	2,761
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	2,764
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	9,860
Financing Receivable, Revolving	1,395
Mortgage Loans, Gross	$ 19,088	$ 19,313
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	$ 264
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	762
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,223
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	2,470
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	2,448
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	9,176
Financing Receivable, Revolving	1,310
Mortgage Loans, Gross	$ 17,653
Loans Receivable Agricultural Mortgage Percentage	92.50%
Agricultural Mortgage Loans | 65% to 75%
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	8
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	51
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	268
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	316
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	608
Financing Receivable, Revolving	80
Mortgage Loans, Gross	$ 1,331
Loans Receivable Agricultural Mortgage Percentage	7.00%
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	23
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	4
Mortgage Loans, Gross	$ 39
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	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	64
Financing Receivable, Revolving	1
Mortgage Loans, Gross	$ 65
Loans Receivable Agricultural Mortgage Percentage	0.30%