Investments (Credit Quality Indicators) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Recording investment gross of allowance for credit losses	$ 58,785	$ 65,660
Held-for-sale
Financing Receivable, Credit Quality Indicator [Line Items]
Recording investment gross of allowance for credit losses	6,580
Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	7,069	6,021
One Years Prior	3,654	10,264
Two Years Prior	7,917	9,069
Three Years Prior	7,963	7,219
Four Years Prior	5,109	6,831
Prior	20,855	21,332
Revolving loans	0
Recording investment gross of allowance for credit losses	52,567	60,736
Commercial Mortgage Loans | ≥ 1.2X
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	6,803	5,901
One Years Prior	3,356	9,429
Two Years Prior	6,828	8,587
Three Years Prior	7,384	6,954
Four Years Prior	4,445	6,382
Prior	16,864	18,904
Revolving loans	0
Recording investment gross of allowance for credit losses	45,680	56,157
Commercial Mortgage Loans | 1.0X to 1.2X
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	266	118
One Years Prior	154	711
Two Years Prior	662	383
Three Years Prior	478	263
Four Years Prior	234	384
Prior	2,069	1,719
Revolving loans	0
Recording investment gross of allowance for credit losses	3,863	3,578
Commercial Mortgage Loans | Less than 1.0X
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	0	2
One Years Prior	144	124
Two Years Prior	427	99
Three Years Prior	101	2
Four Years Prior	430	65
Prior	1,922	709
Revolving loans	0
Recording investment gross of allowance for credit losses	3,024	1,001
Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	2,050	964
One Years Prior	895	545
Two Years Prior	528	388
Three Years Prior	371	530
Four Years Prior	370	367
Prior	1,226	1,254
Revolving loans	80
Recording investment gross of allowance for credit losses	5,520	4,048
Agricultural property loans | ≥ 1.2X
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	2,007	941
One Years Prior	870	544
Two Years Prior	517	381
Three Years Prior	364	468
Four Years Prior	312	308
Prior	1,121	1,202
Revolving loans	80
Recording investment gross of allowance for credit losses	5,271	3,844
Agricultural property loans | 1.0X to 1.2X
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	43	23
One Years Prior	25	0
Two Years Prior	10	1
Three Years Prior	1	59
Four Years Prior	58	1
Prior	41	40
Revolving loans	0
Recording investment gross of allowance for credit losses	178	124
Agricultural property loans | Less than 1.0X
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	0	0
One Years Prior	0	1
Two Years Prior	1	6
Three Years Prior	6	3
Four Years Prior	0	58
Prior	64	12
Revolving loans	0
Recording investment gross of allowance for credit losses	71	80
0%-59.99% | Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	1,287	828
One Years Prior	467	2,693
Two Years Prior	2,459	3,217
Three Years Prior	3,211	3,854
Four Years Prior	3,072	3,223
Prior	14,011	15,360
Revolving loans	0
Recording investment gross of allowance for credit losses	24,507	29,175
0%-59.99% | Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	1,958	956
One Years Prior	887	494
Two Years Prior	494	349
Three Years Prior	334	527
Four Years Prior	370	367
Prior	1,226	1,254
Revolving loans	80
Recording investment gross of allowance for credit losses	5,349	3,947
60%-69.99% | Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	3,101	2,678
One Years Prior	1,941	4,981
Two Years Prior	4,124	4,291
Three Years Prior	3,631	2,239
Four Years Prior	1,356	2,667
Prior	4,161	4,058
Revolving loans	0
Recording investment gross of allowance for credit losses	18,314	20,914
60%-69.99% | Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	92	8
One Years Prior	5	51
Two Years Prior	29	39
Three Years Prior	37	3
Four Years Prior	0	0
Prior	0	0
Revolving loans	0
Recording investment gross of allowance for credit losses	163	101
70%-79.99% | Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	2,497	2,492
One Years Prior	1,207	2,587
Two Years Prior	1,327	1,500
Three Years Prior	1,059	1,057
Four Years Prior	631	918
Prior	2,108	1,409
Revolving loans	0
Recording investment gross of allowance for credit losses	8,829	9,963
70%-79.99% | Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	0	0
One Years Prior	0	0
Two Years Prior	0	0
Three Years Prior	0	0
Four Years Prior	0	0
Prior	0	0
Revolving loans	0
Recording investment gross of allowance for credit losses	0	0
80% or greater | Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	184	23
One Years Prior	39	3
Two Years Prior	7	61
Three Years Prior	62	69
Four Years Prior	50	23
Prior	575	505
Revolving loans	0
Recording investment gross of allowance for credit losses	917	684
80% or greater | Agricultural property loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current Year	0	0
One Years Prior	3	0
Two Years Prior	5	0
Three Years Prior	0	0
Four Years Prior	0	0
Prior	0	0
Revolving loans	0
Recording investment gross of allowance for credit losses	$ 8	$ 0