Investments (Credit Quality Indicators) (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Recording investment gross of allowance for credit losses	$ 57,930	$ 56,948
Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	2,434	3,835
One Years Prior	3,785	6,402
Two Years Prior	6,323	3,361
Three Years Prior	3,303	6,779
Four Years Prior	6,747	7,098
Prior	27,895	22,002
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	50,487	49,477
Commercial Mortgage Loans | ≥ 1.2X
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	2,110	3,249
One Years Prior	3,242	6,135
Two Years Prior	6,118	3,013
Three Years Prior	3,126	5,749
Four Years Prior	5,977	6,505
Prior	24,297	18,318
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	44,870	42,969
Commercial Mortgage Loans | 1.0 - 1.2x
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	97	586
One Years Prior	366	252
Two Years Prior	134	164
Three Years Prior	72	454
Four Years Prior	428	383
Prior	2,037	2,183
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	3,134	4,022
Commercial Mortgage Loans | Less than 1.0x
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	227	0
One Years Prior	177	15
Two Years Prior	71	184
Three Years Prior	105	576
Four Years Prior	342	210
Prior	1,561	1,501
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	2,483	2,486
Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	200	1,606
One Years Prior	1,572	2,079
Two Years Prior	2,068	861
Three Years Prior	844	508
Four Years Prior	498	347
Prior	1,616	1,382
Revolving Loans	86	74
Recording investment gross of allowance for credit losses	6,884	6,857
Agricultural property loans | ≥ 1.2X
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	195	1,593
One Years Prior	1,559	2,035
Two Years Prior	2,025	781
Three Years Prior	813	507
Four Years Prior	497	323
Prior	1,528	1,272
Revolving Loans	86	74
Recording investment gross of allowance for credit losses	6,703	6,585
Agricultural property loans | 1.0 - 1.2x
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	0	5
One Years Prior	5	44
Two Years Prior	43	80
Three Years Prior	31	0
Four Years Prior	0	6
Prior	75	68
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	154	203
Agricultural property loans | Less than 1.0x
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	5	8
One Years Prior	8	0
Two Years Prior	0	0
Three Years Prior	0	1
Four Years Prior	1	18
Prior	13	42
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	27	69
0%-59.99% | Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	774	971
One Years Prior	672	1,747
Two Years Prior	1,693	1,282
Three Years Prior	1,336	2,831
Four Years Prior	3,114	4,697
Prior	18,602	15,111
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	26,191	26,639
0%-59.99% | Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	131	931
One Years Prior	901	1,994
Two Years Prior	2,005	853
Three Years Prior	768	461
Four Years Prior	456	326
Prior	1,563	1,348
Revolving Loans	86	74
Recording investment gross of allowance for credit losses	5,910	5,987
60%-69.99% | Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	1,021	1,997
One Years Prior	2,040	3,502
Two Years Prior	3,533	1,553
Three Years Prior	1,467	2,804
Four Years Prior	2,247	1,732
Prior	5,791	3,780
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	16,099	15,368
60%-69.99% | Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	69	675
One Years Prior	671	85
Two Years Prior	63	8
Three Years Prior	76	47
Four Years Prior	27	8
Prior	53	0
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	959	823
70%-79.99% | Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	562	865
One Years Prior	1,037	1,127
Two Years Prior	1,073	519
Three Years Prior	493	1,025
Four Years Prior	1,268	645
Prior	1,745	1,445
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	6,178	5,626
70%-79.99% | Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	0	0
One Years Prior	0	0
Two Years Prior	0	0
Three Years Prior	0	0
Four Years Prior	15	0
Prior	0	0
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	15	0
80% or greater | Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	77	2
One Years Prior	36	26
Two Years Prior	24	7
Three Years Prior	7	119
Four Years Prior	118	24
Prior	1,757	1,666
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	2,019	1,844
80% or greater | Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Fiscal Year	0	0
One Years Prior	0	0
Two Years Prior	0	0
Three Years Prior	0	0
Four Years Prior	0	13
Prior	0	34
Revolving Loans	0	0
Recording investment gross of allowance for credit losses	$ 0	$ 47