CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Statement of Financial Position [Abstract]
Debt Securities, Held-to-maturity, Fair Value	$ 65,911	$ 68,989
Debt Securities, Available-for-sale, Amortized Cost	$ 3,669,996	$ 3,512,652
Common Stock, No Par Value	$ 0	$ 0
Common Stock, Shares Authorized	160,000,000	160,000,000
Common Stock, Shares, Issued	104,281,794	104,281,794
Treasury Stock, Common, Shares	8,524,544	8,786,954

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

FIRST FINANCIAL BANCORP /OH/ 10-Q