LEASES (Narrative) (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026 USD ($) branch	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($) branch	Sep. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
Leases [Abstract]
Number of branches \| branch	407		407
Number of branches owned \| branch	279		279
Number of branches leased \| branch	128		128
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets 1		Other assets 1		Other assets 1
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Premises, equipment and software, net		Premises, equipment and software, net		Premises, equipment and software, net
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other liabilities 1		Other liabilities 1		Other liabilities 1
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Long-term debt		Long-term debt		Long-term debt
Operating lease income \| $	$ 4	$ 4	$ 12	$ 11
Sales-type or direct financing leases \| $	331		331		$ 367
Sales-type or direct financing leases income \| $	$ 4	$ 5	$ 14	$ 14

Indicates line item in statement of financial position that includes finance lease liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-2

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Indicates line item in statement of financial position that includes finance lease right-of-use asset.

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- Definition

Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479773/842-30-50-5

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 270
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482964/270-10-50-6A

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479016/842-30-45-3

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Indicates line item in statement of financial position that includes operating lease liability.

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Indicates line item in statement of financial position that includes operating lease right-of-use asset.

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- Definition

Present value of lease payments not yet received by lessor and amount expected to be derived from underlying asset, following end of lease term guaranteed by lessee or other third party unrelated to lessor, from sales-type and direct financing leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479773/842-30-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479773/842-30-50-10

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- Definition

Amount of profit (loss) for sales-type lease and (loss) for direct financing lease recognized at commencement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)(1)
-Publisher FASB
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- Definition

Number of Branches

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Number of Branches Leased

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Number of Branches Owned

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