INVESTMENTS - Credit Quality (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Commercial Mortgage Loans
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	$ 2,157	$ 1,615
Fiscal year before current fiscal year	1,570	814
Two years before current fiscal year	819	1,267
Three years before current fiscal year	1,253	1,204
Four years before current fiscal year	1,065	2,563
Prior	4,570	3,028
Total	11,434	10,491
Total	11,434	10,491
Non-accruing Loans	0	0
Non-accruing Loans with No Allowance	0	0
Interest Income on Non-accruing Loans	0	0
Commercial Mortgage Loans | Past Due
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	0	162
Commercial Mortgage Loans | 30-59 Days
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	0	162
Commercial Mortgage Loans | 60-89 Days
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	0	0
Commercial Mortgage Loans | 90 Days or  More
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	0	0
Commercial Mortgage Loans | Current
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	11,434	10,329
Commercial Mortgage Loans | Greater than 2.0x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	1,143	1,230
Fiscal year before current fiscal year	1,243	492
Two years before current fiscal year	210	772
Three years before current fiscal year	772	268
Four years before current fiscal year	485	1,942
Prior	2,218	1,230
Total	6,071	5,934
Commercial Mortgage Loans | 1.8x to 2.0x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	185	227
Fiscal year before current fiscal year	135	83
Two years before current fiscal year	250	118
Three years before current fiscal year	46	378
Four years before current fiscal year	161	184
Prior	372	329
Total	1,149	1,319
Commercial Mortgage Loans | 1.5x to 1.8x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	275	98
Fiscal year before current fiscal year	97	138
Two years before current fiscal year	284	187
Three years before current fiscal year	211	479
Four years before current fiscal year	166	437
Prior	919	616
Total	1,952	1,955
Commercial Mortgage Loans | 1.2x to 1.5x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	264	60
Fiscal year before current fiscal year	95	57
Two years before current fiscal year	75	154
Three years before current fiscal year	101	79
Four years before current fiscal year	253	0
Prior	701	658
Total	1,489	1,008
Commercial Mortgage Loans | 1.0x to 1.2x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	290	0
Fiscal year before current fiscal year	0	44
Two years before current fiscal year	0	0
Three years before current fiscal year	88	0
Four years before current fiscal year	0	0
Prior	287	123
Total	665	167
Commercial Mortgage Loans | Less than 1.0x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	0	0
Fiscal year before current fiscal year	0	0
Two years before current fiscal year	0	36
Three years before current fiscal year	35	0
Four years before current fiscal year	0	0
Prior	73	72
Total	108	108
Commercial Mortgage Loans | 0% - 50%
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	0	0
Fiscal year before current fiscal year	0	0
Two years before current fiscal year	0	0
Three years before current fiscal year	184	324
Four years before current fiscal year	293	170
Prior	992	505
Total	1,469	999
Commercial Mortgage Loans | 50% - 70%
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	1,967	1,294
Fiscal year before current fiscal year	1,334	357
Two years before current fiscal year	407	803
Three years before current fiscal year	619	656
Four years before current fiscal year	491	2,190
Prior	2,533	1,697
Total	7,351	6,997
Commercial Mortgage Loans | 70% - 90%
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	190	321
Fiscal year before current fiscal year	236	457
Two years before current fiscal year	412	452
Three years before current fiscal year	415	219
Four years before current fiscal year	276	203
Prior	972	538
Total	2,501	2,190
Commercial Mortgage Loans | 90% plus
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	0	0
Fiscal year before current fiscal year	0	0
Two years before current fiscal year	0	12
Three years before current fiscal year	35	5
Four years before current fiscal year	5	0
Prior	73	288
Total	113	305
Agricultural Mortgage Loans
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	380	495
Fiscal year before current fiscal year	480	264
Two years before current fiscal year	230	333
Three years before current fiscal year	255	259
Four years before current fiscal year	206	360
Prior	1,093	1,021
Total	2,644	2,732
Total	2,628	2,732
Non-accruing Loans	16	0
Non-accruing Loans with No Allowance	0	0
Interest Income on Non-accruing Loans	0	0
Agricultural Mortgage Loans | Past Due
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	27	112
Agricultural Mortgage Loans | 30-59 Days
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	1	76
Agricultural Mortgage Loans | 60-89 Days
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	1	7
Agricultural Mortgage Loans | 90 Days or  More
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	25	29
Agricultural Mortgage Loans | Current
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	2,601	2,620
Agricultural Mortgage Loans | Greater than 2.0x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	49	67
Fiscal year before current fiscal year	64	26
Two years before current fiscal year	25	36
Three years before current fiscal year	22	38
Four years before current fiscal year	24	71
Prior	210	167
Total	394	405
Agricultural Mortgage Loans | 1.8x to 2.0x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	52	38
Fiscal year before current fiscal year	37	35
Two years before current fiscal year	25	14
Three years before current fiscal year	14	15
Four years before current fiscal year	14	20
Prior	70	82
Total	212	204
Agricultural Mortgage Loans | 1.5x to 1.8x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	43	117
Fiscal year before current fiscal year	113	38
Two years before current fiscal year	28	41
Three years before current fiscal year	22	45
Four years before current fiscal year	41	52
Prior	193	209
Total	440	502
Agricultural Mortgage Loans | 1.2x to 1.5x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	161	183
Fiscal year before current fiscal year	179	120
Two years before current fiscal year	112	141
Three years before current fiscal year	116	90
Four years before current fiscal year	72	142
Prior	355	313
Total	995	989
Agricultural Mortgage Loans | 1.0x to 1.2x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	75	86
Fiscal year before current fiscal year	83	35
Two years before current fiscal year	31	93
Three years before current fiscal year	77	70
Four years before current fiscal year	54	57
Prior	226	233
Total	546	574
Agricultural Mortgage Loans | Less than 1.0x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	0	4
Fiscal year before current fiscal year	4	10
Two years before current fiscal year	9	8
Three years before current fiscal year	4	1
Four years before current fiscal year	1	18
Prior	39	17
Total	57	58
Agricultural Mortgage Loans | 0% - 50%
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	180	218
Fiscal year before current fiscal year	212	135
Two years before current fiscal year	128	169
Three years before current fiscal year	129	157
Four years before current fiscal year	119	236
Prior	738	652
Total	1,506	1,567
Agricultural Mortgage Loans | 50% - 70%
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	200	277
Fiscal year before current fiscal year	268	129
Two years before current fiscal year	102	161
Three years before current fiscal year	126	102
Four years before current fiscal year	87	124
Prior	338	351
Total	1,121	1,144
Agricultural Mortgage Loans | 70% - 90%
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	0	0
Fiscal year before current fiscal year	0	0
Two years before current fiscal year	0	3
Three years before current fiscal year	0	0
Four years before current fiscal year	0	0
Prior	17	18
Total	17	21
Agricultural Mortgage Loans | 90% plus
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	0	0
Fiscal year before current fiscal year	0	0
Two years before current fiscal year	0	0
Three years before current fiscal year	0	0
Four years before current fiscal year	0	0
Prior	0	0
Total	0	0
Mortgages Loan
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	2,537	2,110
Fiscal year before current fiscal year	2,050	1,078
Two years before current fiscal year	1,049	1,600
Three years before current fiscal year	1,508	1,463
Four years before current fiscal year	1,271	2,923
Prior	5,663	4,049
Total	14,078	13,223
Total	14,062	13,223
Non-accruing Loans	16	0
Non-accruing Loans with No Allowance	0	0
Interest Income on Non-accruing Loans	0	0
Mortgages Loan | Past Due
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	27	274
Mortgages Loan | 30-59 Days
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	1	238
Mortgages Loan | 60-89 Days
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	1	7
Mortgages Loan | 90 Days or  More
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	25	29
Mortgages Loan | Current
Financing Receivable, before Allowance for Credit Loss [Abstract]
Total	14,035	12,949
Mortgages Loan | Greater than 2.0x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	1,192	1,297
Fiscal year before current fiscal year	1,307	518
Two years before current fiscal year	235	808
Three years before current fiscal year	794	306
Four years before current fiscal year	509	2,013
Prior	2,428	1,397
Total	6,465	6,339
Mortgages Loan | 1.8x to 2.0x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	237	265
Fiscal year before current fiscal year	172	118
Two years before current fiscal year	275	132
Three years before current fiscal year	60	393
Four years before current fiscal year	175	204
Prior	442	411
Total	1,361	1,523
Mortgages Loan | 1.5x to 1.8x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	318	215
Fiscal year before current fiscal year	210	176
Two years before current fiscal year	312	228
Three years before current fiscal year	233	524
Four years before current fiscal year	207	489
Prior	1,112	825
Total	2,392	2,457
Mortgages Loan | 1.2x to 1.5x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	425	243
Fiscal year before current fiscal year	274	177
Two years before current fiscal year	187	295
Three years before current fiscal year	217	169
Four years before current fiscal year	325	142
Prior	1,056	971
Total	2,484	1,997
Mortgages Loan | 1.0x to 1.2x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	365	86
Fiscal year before current fiscal year	83	79
Two years before current fiscal year	31	93
Three years before current fiscal year	165	70
Four years before current fiscal year	54	57
Prior	513	356
Total	1,211	741
Mortgages Loan | Less than 1.0x
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	0	4
Fiscal year before current fiscal year	4	10
Two years before current fiscal year	9	44
Three years before current fiscal year	39	1
Four years before current fiscal year	1	18
Prior	112	89
Total	165	166
Mortgages Loan | 0% - 50%
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	180	218
Fiscal year before current fiscal year	212	135
Two years before current fiscal year	128	169
Three years before current fiscal year	313	481
Four years before current fiscal year	412	406
Prior	1,730	1,157
Total	2,975	2,566
Mortgages Loan | 50% - 70%
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	2,167	1,571
Fiscal year before current fiscal year	1,602	486
Two years before current fiscal year	509	964
Three years before current fiscal year	745	758
Four years before current fiscal year	578	2,314
Prior	2,871	2,048
Total	8,472	8,141
Mortgages Loan | 70% - 90%
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	190	321
Fiscal year before current fiscal year	236	457
Two years before current fiscal year	412	455
Three years before current fiscal year	415	219
Four years before current fiscal year	276	203
Prior	989	556
Total	2,518	2,211
Mortgages Loan | 90% plus
Financing Receivable, before Allowance for Credit Loss [Abstract]
Current fiscal year	0	0
Fiscal year before current fiscal year	0	0
Two years before current fiscal year	0	12
Three years before current fiscal year	35	5
Four years before current fiscal year	5	0
Prior	73	288
Total	$ 113	$ 305