LOANS AND LEASES - Origination Year (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	$ 5,472	$ 6,587
Fiscal year before current fiscal year	6,524	4,518
Two years before current fiscal year	4,077	3,256
Three years before current fiscal year	2,776	1,952
Four years before current fiscal year	1,654	1,579
Prior	4,945	4,130
Revolving Loans Amortized Cost Basis	3,332	2,946
Total Loans and Leases	28,780	24,968
Current
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	28,610	24,815
Past due
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	170	153
Total commercial loans and leases
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	2,892	3,786
Fiscal year before current fiscal year	3,625	2,779
Two years before current fiscal year	2,524	2,484
Three years before current fiscal year	2,106	1,486
Four years before current fiscal year	1,316	1,200
Prior	3,465	2,858
Revolving Loans Amortized Cost Basis	2,252	1,872
Total Loans and Leases	18,180	16,465
Total commercial loans and leases | Current
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	18,095	16,385
Total commercial loans and leases | Past due
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	85	80
Total commercial loans and leases | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	1,439	1,893
Fiscal year before current fiscal year	2,216	1,818
Two years before current fiscal year	1,701	1,620
Three years before current fiscal year	1,446	980
Four years before current fiscal year	872	895
Prior	2,888	2,498
Revolving Loans Amortized Cost Basis	279	195
Total Loans and Leases	10,841	9,899
Total commercial loans and leases | Commercial real estate | Current
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	10,784	9,840
Total commercial loans and leases | Commercial real estate | Past due
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	57	59
Total commercial loans and leases | Commercial real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	1,400	1,878
Fiscal year before current fiscal year	2,166	1,782
Two years before current fiscal year	1,628	1,503
Three years before current fiscal year	1,335	830
Four years before current fiscal year	713	743
Prior	2,489	2,171
Revolving Loans Amortized Cost Basis	253	183
Total Loans and Leases	9,984	9,090
Total commercial loans and leases | Commercial real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	35	15
Fiscal year before current fiscal year	34	21
Two years before current fiscal year	61	89
Three years before current fiscal year	75	105
Four years before current fiscal year	130	107
Prior	232	175
Revolving Loans Amortized Cost Basis	6	9
Total Loans and Leases	573	521
Total commercial loans and leases | Commercial real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	4	0
Fiscal year before current fiscal year	16	15
Two years before current fiscal year	12	28
Three years before current fiscal year	36	45
Four years before current fiscal year	29	45
Prior	167	152
Revolving Loans Amortized Cost Basis	20	3
Total Loans and Leases	284	288
Total commercial loans and leases | Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	1,277	1,672
Fiscal year before current fiscal year	1,254	849
Two years before current fiscal year	740	763
Three years before current fiscal year	587	450
Four years before current fiscal year	402	263
Prior	531	355
Revolving Loans Amortized Cost Basis	1,918	1,625
Total Loans and Leases	6,709	5,977
Total commercial loans and leases | Commercial and industrial | Current
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	6,684	5,958
Total commercial loans and leases | Commercial and industrial | Past due
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	25	19
Total commercial loans and leases | Commercial and industrial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	1,270	1,663
Fiscal year before current fiscal year	1,232	833
Two years before current fiscal year	714	731
Three years before current fiscal year	530	386
Four years before current fiscal year	346	184
Prior	439	296
Revolving Loans Amortized Cost Basis	1,810	1,509
Total Loans and Leases	6,341	5,602
Total commercial loans and leases | Commercial and industrial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	3	8
Fiscal year before current fiscal year	8	12
Two years before current fiscal year	20	18
Three years before current fiscal year	49	7
Four years before current fiscal year	17	37
Prior	37	42
Revolving Loans Amortized Cost Basis	57	52
Total Loans and Leases	191	176
Total commercial loans and leases | Commercial and industrial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	4	1
Fiscal year before current fiscal year	14	4
Two years before current fiscal year	6	14
Three years before current fiscal year	8	57
Four years before current fiscal year	39	42
Prior	55	17
Revolving Loans Amortized Cost Basis	51	64
Total Loans and Leases	177	199
Total commercial loans and leases | Commercial leases
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	117	182
Fiscal year before current fiscal year	155	112
Two years before current fiscal year	83	101
Three years before current fiscal year	73	56
Four years before current fiscal year	42	42
Prior	33	2
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	503	495
Total commercial loans and leases | Commercial leases | Current
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	501	493
Total commercial loans and leases | Commercial leases | Past due
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	2	2
Total commercial loans and leases | Commercial leases | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	111	182
Fiscal year before current fiscal year	153	109
Two years before current fiscal year	76	98
Three years before current fiscal year	73	53
Four years before current fiscal year	41	39
Prior	33	1
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	487	482
Total commercial loans and leases | Commercial leases | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	2	0
Fiscal year before current fiscal year	1	1
Two years before current fiscal year	0	0
Three years before current fiscal year	0	2
Four years before current fiscal year	1	3
Prior	0	1
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	4	7
Total commercial loans and leases | Commercial leases | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	4	0
Fiscal year before current fiscal year	1	2
Two years before current fiscal year	7	3
Three years before current fiscal year	0	1
Four years before current fiscal year	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	12	6
Total commercial loans and leases | Other
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	59	39
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	13	3
Revolving Loans Amortized Cost Basis	55	52
Total Loans and Leases	127	94
Total commercial loans and leases | Other | Current
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	126	94
Total commercial loans and leases | Other | Past due
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	1	0
Total commercial loans and leases | Other | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	59	39
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	13	3
Revolving Loans Amortized Cost Basis	55	52
Total Loans and Leases	127	94
Total consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	2,580	2,801
Fiscal year before current fiscal year	2,899	1,739
Two years before current fiscal year	1,553	772
Three years before current fiscal year	670	466
Four years before current fiscal year	338	379
Prior	1,480	1,272
Revolving Loans Amortized Cost Basis	1,080	1,074
Total Loans and Leases	10,600	8,503
Total consumer loans | Current
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	10,515	8,430
Total consumer loans | Past due
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	85	73
Total consumer loans | Direct installment
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	731	978
Fiscal year before current fiscal year	917	538
Two years before current fiscal year	474	216
Three years before current fiscal year	172	126
Four years before current fiscal year	96	96
Prior	407	422
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	2,797	2,376
Total consumer loans | Direct installment | Current
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	731	978
Fiscal year before current fiscal year	917	538
Two years before current fiscal year	473	215
Three years before current fiscal year	171	125
Four years before current fiscal year	95	96
Prior	397	412
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	2,784	2,364
Total consumer loans | Direct installment | Past due
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	0	0
Fiscal year before current fiscal year	0	0
Two years before current fiscal year	1	1
Three years before current fiscal year	1	1
Four years before current fiscal year	1	0
Prior	10	10
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	13	12
Total consumer loans | Residential mortgages
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	1,101	1,281
Fiscal year before current fiscal year	1,563	933
Two years before current fiscal year	889	393
Three years before current fiscal year	391	155
Four years before current fiscal year	136	215
Prior	879	677
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	4,959	3,654
Total consumer loans | Residential mortgages | Current
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	1,101	1,280
Fiscal year before current fiscal year	1,560	932
Two years before current fiscal year	886	392
Three years before current fiscal year	389	152
Four years before current fiscal year	133	212
Prior	848	652
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	4,917	3,620
Total consumer loans | Residential mortgages | Past due
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	0	1
Fiscal year before current fiscal year	3	1
Two years before current fiscal year	3	1
Three years before current fiscal year	2	3
Four years before current fiscal year	3	3
Prior	31	25
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	42	34
Total consumer loans | Indirect installment
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	685	522
Fiscal year before current fiscal year	401	265
Two years before current fiscal year	188	159
Three years before current fiscal year	104	180
Four years before current fiscal year	101	65
Prior	50	36
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	1,529	1,227
Total consumer loans | Indirect installment | Current
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	683	516
Fiscal year before current fiscal year	394	262
Two years before current fiscal year	186	157
Three years before current fiscal year	102	178
Four years before current fiscal year	100	64
Prior	49	35
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	1,514	1,212
Total consumer loans | Indirect installment | Past due
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	2	6
Fiscal year before current fiscal year	7	3
Two years before current fiscal year	2	2
Three years before current fiscal year	2	2
Four years before current fiscal year	1	1
Prior	1	1
Revolving Loans Amortized Cost Basis	0	0
Total Loans and Leases	15	15
Total consumer loans | Consumer lines of credit
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	63	20
Fiscal year before current fiscal year	18	3
Two years before current fiscal year	2	4
Three years before current fiscal year	3	5
Four years before current fiscal year	5	3
Prior	144	137
Revolving Loans Amortized Cost Basis	1,080	1,074
Total Loans and Leases	1,315	1,246
Total consumer loans | Consumer lines of credit | Current
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	63	20
Fiscal year before current fiscal year	18	3
Two years before current fiscal year	2	4
Three years before current fiscal year	3	5
Four years before current fiscal year	4	3
Prior	132	127
Revolving Loans Amortized Cost Basis	1,078	1,072
Total Loans and Leases	1,300	1,234
Total consumer loans | Consumer lines of credit | Past due
Financing Receivable, Credit Quality Indicator [Line Items]
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	1	0
Prior	12	10
Revolving Loans Amortized Cost Basis	2	2
Total Loans and Leases	$ 15	$ 12