Investments (Credit Quality Indicators) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Recording investment gross of allowance for credit losses	$ 63,176	$ 59,765
Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	6,116	5,733
One Years Prior	5,264	3,712
Two Years Prior	3,666	6,286
Three Years Prior	6,125	3,275
Four Years Prior	3,011	6,573
Prior	30,122	26,180
Revolving Loans	11	0
Recording investment gross of allowance for credit losses	54,315	51,759
Commercial Mortgage Loans | ≥ 1.2X
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	5,436	5,237
One Years Prior	4,779	3,194
Two Years Prior	3,140	6,122
Three Years Prior	6,022	3,182
Four Years Prior	2,853	5,988
Prior	27,250	23,196
Revolving Loans	11	0
Recording investment gross of allowance for credit losses	49,491	46,919
Commercial Mortgage Loans | 1.0 - 1.2x
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	597	346
One Years Prior	335	366
Two Years Prior	374	82
Three Years Prior	52	38
Four Years Prior	104	265
Prior	1,556	1,713
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	3,018	2,810
Commercial Mortgage Loans | Less than 1.0x
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	83	150
One Years Prior	150	152
Two Years Prior	152	82
Three Years Prior	51	55
Four Years Prior	54	320
Prior	1,316	1,271
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	1,806	2,030
Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	402	953
One Years Prior	935	1,548
Two Years Prior	1,538	2,052
Three Years Prior	2,029	824
Four Years Prior	810	490
Prior	1,840	1,485
Revolving Loans	184	74
Recording investment gross of allowance for credit losses	7,738	7,426
Agricultural property loans | ≥ 1.2X
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	394	948
One Years Prior	866	1,535
Two Years Prior	1,004	2,040
Three Years Prior	1,976	750
Four Years Prior	737	489
Prior	1,632	1,290
Revolving Loans	132	74
Recording investment gross of allowance for credit losses	6,741	7,126
Agricultural property loans | 1.0 - 1.2x
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	8	0
One Years Prior	64	5
Two Years Prior	526	4
Three Years Prior	45	58
Four Years Prior	57	0
Prior	153	151
Revolving Loans	52	0
Recording investment gross of allowance for credit losses	905	218
Agricultural property loans | Less than 1.0x
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	0	5
One Years Prior	5	8
Two Years Prior	8	8
Three Years Prior	8	16
Four Years Prior	16	1
Prior	55	44
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	92	82
0%-59.99% | Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	1,265	1,822
One Years Prior	1,631	911
Two Years Prior	1,021	2,264
Three Years Prior	2,186	1,437
Four Years Prior	1,234	3,205
Prior	17,757	16,569
Revolving Loans	11	0
Recording investment gross of allowance for credit losses	25,105	26,208
0%-59.99% | Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	344	360
One Years Prior	374	880
Two Years Prior	897	2,027
Three Years Prior	2,019	774
Four Years Prior	686	455
Prior	1,789	1,481
Revolving Loans	132	74
Recording investment gross of allowance for credit losses	6,241	6,051
60%-69.99% | Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	4,334	2,765
One Years Prior	2,585	1,440
Two Years Prior	1,040	2,541
Three Years Prior	2,355	1,107
Four Years Prior	1,048	2,146
Prior	5,879	4,530
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	17,241	14,529
60%-69.99% | Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	58	586
One Years Prior	555	668
Two Years Prior	124	25
Three Years Prior	10	50
Four Years Prior	53	20
Prior	43	4
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	843	1,353
70%-79.99% | Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	467	1,001
One Years Prior	911	1,004
Two Years Prior	1,110	1,278
Three Years Prior	1,355	401
Four Years Prior	447	1,013
Prior	2,258	2,277
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	6,548	6,974
70%-79.99% | Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	0	7
One Years Prior	0	0
Two Years Prior	0	0
Three Years Prior	0	0
Four Years Prior	0	0
Prior	3	0
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	3	7
80% or greater | Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	50	145
One Years Prior	137	357
Two Years Prior	495	203
Three Years Prior	229	330
Four Years Prior	282	209
Prior	4,228	2,804
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	5,421	4,048
80% or greater | Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	0	0
One Years Prior	6	0
Two Years Prior	517	0
Three Years Prior	0	0
Four Years Prior	71	15
Prior	5	0
Revolving Loans	52	0
Recording investment gross of allowance for credit losses	$ 651	$ 15