Financing Receivable, Impaired, Interest Income Recorded on Nonaccrual Loans

No definition available.

Name:	ffbc_FinancingReceivableImpairedInterestIncomeRecordedOnNonaccrualLoans
Namespace Prefix:	ffbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Impaired receivables, Number of Contracts

+ References

No definition available.

+ Details

Name:	ffbc_ImpairedReceivablesNumberOfContracts
Namespace Prefix:	ffbc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Restructured Loans, Loan Relationships, Review Threshold Amount Minimum for commercial and other loans greater than $250,000

+ References

No definition available.

+ Details

Name:	ffbc_RestructuredLoansLoanRelationshipsReviewThresholdAmountMinimum
Namespace Prefix:	ffbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

+ Details

Name:	us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-34

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 44
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-44

+ Details

Name:	us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-11

+ Details

Name:	us-gaap_RealEstateAcquiredThroughForeclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Unused amount of commitments to extend credit to customers.

+ References

No definition available.

+ Details

Name:	us-gaap_UnusedCommitmentsToExtendCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ffbc_FinancialDifficultyModificationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

LOANS AND LEASES - Additional Information (Details)	3 Months Ended		9 Months Ended
LOANS AND LEASES - Additional Information (Details)	Sep. 30, 2025 USD ($) loans	Sep. 30, 2024 USD ($) loans	Sep. 30, 2025 USD ($) loans	Sep. 30, 2024 USD ($) loans	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 600,000	$ 100,000	$ 1,800,000	$ 500,000
Real Estate Acquired Through Foreclosure	111,000	30,000	111,000	30,000	$ 204,000	$ 64,000	$ 30,000	$ 106,000
Unused Commitments to Extend Credit	$ 4,074,151,000		$ 4,074,151,000			$ 3,750,657,000
Nonaccrual loans		$ 200,000		$ 800,000
Impaired receivables, Number of Contracts \| loans	6	1	19	6
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructured Loans, Loan Relationships, Review Threshold Amount Minimum			$ 250,000
Financial Difficulty Modification
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unused Commitments to Extend Credit	$ 0	$ 0	$ 0	$ 0