BORROWINGS - Schedule of Junior Subordinated Debt Trusts (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2025	Dec. 31, 2024
Subordinated Borrowing [Line Items]
Junior subordinated debt	$ 74	$ 73
Trust Preferred Securities
Subordinated Borrowing [Line Items]
Junior subordinated debt	$ 77
Basis points, interest rate, type [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	6.23%
Basis points, interest rate, type [Extensible Enumeration]	Secured Overnight Financing Rate (SOFR) [Member]
Basis points	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	5.90%
Basis points, interest rate, type [Extensible Enumeration]	Secured Overnight Financing Rate (SOFR) [Member]
Basis points	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	6.02%
Basis points, interest rate, type [Extensible Enumeration]	Secured Overnight Financing Rate (SOFR) [Member]
Basis points	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	6.06%
Basis points, interest rate, type [Extensible Enumeration]	Secured Overnight Financing Rate (SOFR) [Member]
Basis points	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

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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

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-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
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- Definition

Indicates type of variable interest rate on debt instrument.

+ References

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-Topic 942
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-Section 50
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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
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-Name Accounting Standards Codification
-Section S99
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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