LOANS (excluding covered loans) - Additional Information (Detail) (Commercial, Non Covered Loans, USD $)	6 Months Ended
Jun. 30, 2012
Commercial \| Non Covered Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum loans reviewed to determine if a specific allowance is necessary	$ 250,000

Minimum Loan Amount Required to Measure Impairment Allowance

No definition available.

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