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LONG-TERM BORROWINGS - Schedule of Junior Subordinated Debt Trusts (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2025 | Dec. 31, 2024
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | $ 74 | $ 73
Trust Preferred Securities |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | $ 77 |
Rate Reset Factor [Extensible Enumeration] | Secured Overnight Financing Rate (SOFR) [Member] |
Common Securities |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | $ 3 |
F.N.B. Statutory Trust II |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | $ 22 |
Interest Rate | 5.63% |
Rate Reset Factor [Extensible Enumeration] | Secured Overnight Financing Rate (SOFR) [Member] |
Rate Reset Factor | 1.65% |
F.N.B. Statutory Trust II | Trust Preferred Securities |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | $ 22 |
F.N.B. Statutory Trust II | Common Securities |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | 1 |
Yadkin Valley Statutory Trust I |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | $ 23 |
Interest Rate | 5.30% |
Rate Reset Factor [Extensible Enumeration] | Secured Overnight Financing Rate (SOFR) [Member] |
Rate Reset Factor | 1.32% |
Yadkin Valley Statutory Trust I | Trust Preferred Securities |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | $ 25 |
Yadkin Valley Statutory Trust I | Common Securities |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | 1 |
FNB Financial Services Capital Trust I |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | $ 24 |
Interest Rate | 5.41% |
Rate Reset Factor [Extensible Enumeration] | Secured Overnight Financing Rate (SOFR) [Member] |
Rate Reset Factor | 1.46% |
FNB Financial Services Capital Trust I | Trust Preferred Securities |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | $ 25 |
FNB Financial Services Capital Trust I | Common Securities |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | 1 |
Patapsco Statutory Trust I |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | $ 5 |
Interest Rate | 5.46% |
Rate Reset Factor [Extensible Enumeration] | Secured Overnight Financing Rate (SOFR) [Member] |
Rate Reset Factor | 1.48% |
Patapsco Statutory Trust I | Trust Preferred Securities |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | $ 5 |
Patapsco Statutory Trust I | Common Securities |  |
Subordinated Borrowing [Line Items] |  |
Junior subordinated debt | $ 0 |

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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482949/835-30-55-8 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)(a)(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482900/835-30-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482925/835-30-45-2 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-6 + Details
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- Definition Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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