LOANS, LEASES, AND ALLOWANCE FOR CREDIT LOSSES (Summary of Gross Charge-offs by Loan Origination Year) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Gross charge-offs
2025/2024	$ 1	$ 0
2024/2023	2	10
2023/2022	5	24
2022/2021	3	2
2021/2020	7	0
Prior	18	12
Revolving loans gross charge-offs	85	39
Revolving loans converted to term loans gross charge-offs	1	4
Total	122	91
Commercial
Gross charge-offs
2025/2024	0	0
2024/2023	2	3
2023/2022	2	20
2022/2021	3	2
2021/2020	6	0
Prior	14	9
Revolving loans gross charge-offs	75	30
Revolving loans converted to term loans gross charge-offs	1	4
Total	103	68
Commercial \| Commercial and industrial
Gross charge-offs
2025/2024	0	0
2024/2023	2	3
2023/2022	2	19
2022/2021	3	2
2021/2020	3	0
Prior	13	9
Revolving loans gross charge-offs	75	30
Revolving loans converted to term loans gross charge-offs	1	4
Total	99	67
Commercial \| Owner-occupied
Gross charge-offs
2025/2024	0	0
2024/2023	0	0
2023/2022	0	1
2022/2021	0	0
2021/2020	0	0
Prior	1	0
Revolving loans gross charge-offs	0	0
Revolving loans converted to term loans gross charge-offs	0	0
Total	1	1
Commercial \| Municipal
Gross charge-offs
2025/2024	0
2024/2023	0
2023/2022	0
2022/2021	0
2021/2020	3
Prior	0
Revolving loans gross charge-offs	0
Revolving loans converted to term loans gross charge-offs	0
Total	3
Commercial \| Leasing
Gross charge-offs
2025/2024	0
2024/2023	0
2023/2022	0
2022/2021	0
2021/2020	0
Prior	0
Revolving loans gross charge-offs	0
Revolving loans converted to term loans gross charge-offs	0
Total	0
Commercial real estate
Gross charge-offs
Total	4	11
Commercial real estate \| Term
Gross charge-offs
2025/2024	1	0
2024/2023	0	7
2023/2022	3	4
2022/2021	0	0
2021/2020	0	0
Prior	0	0
Revolving loans gross charge-offs	0	0
Revolving loans converted to term loans gross charge-offs	0	0
Total	4	11
Consumer
Gross charge-offs
2025/2024	0	0
2024/2023	0	0
2023/2022	0	0
2022/2021	0	0
2021/2020	1	0
Prior	4	3
Revolving loans gross charge-offs	10	9
Revolving loans converted to term loans gross charge-offs	0	0
Total	15	12
Consumer \| 1-4 family residential
Gross charge-offs
2025/2024	0	0
2024/2023	0	0
2023/2022	0	0
2022/2021	0	0
2021/2020	1	0
Prior	2	1
Revolving loans gross charge-offs	0	0
Revolving loans converted to term loans gross charge-offs	0	0
Total	3	1
Consumer \| Home equity credit line
Gross charge-offs
2025/2024	0	0
2024/2023	0	0
2023/2022	0	0
2022/2021	0	0
2021/2020	0	0
Prior	0	0
Revolving loans gross charge-offs	2	1
Revolving loans converted to term loans gross charge-offs	0	0
Total	2	1
Consumer \| Bankcard and other revolving plans
Gross charge-offs
2025/2024	0	0
2024/2023	0	0
2023/2022	0	0
2022/2021	0	0
2021/2020	0	0
Prior	0	0
Revolving loans gross charge-offs	8	8
Revolving loans converted to term loans gross charge-offs	0	0
Total	8	8
Consumer \| Other
Gross charge-offs
2025/2024	0	0
2024/2023	0	0
2023/2022	0	0
2022/2021	0	0
2021/2020	0	0
Prior	2	2
Revolving loans gross charge-offs	0	0
Revolving loans converted to term loans gross charge-offs	0	0
Total	$ 2	$ 2

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6A

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