Regulatory Matters (Tables)

12 Months Ended

Dec. 31, 2023

Deposits [Abstract]

Schedule of Regulatory Capital Ratios Under the Basel III Regulatory Capital Framework

As of December 31, 2023 and 2022, the regulatory capital ratios of the Company and Bank under the Basel III regulatory capital framework are as follows:

	Actual					Minimum Capital Required-Basel III Fully Phased-In*					Required to be Considered Well- Capitalized
As of December 31, 2023:	Amount		Ratio			Amount		Ratio			Amount		Ratio
Total Capital to Risk-Weighted Assets:
Consolidated	$	1,697,999		19.62	%	$	908,870		10.50	%	$	865,590		10.00	%
First Financial Bank, N.A	$	1,518,365		17.59	%	$	906,541		10.50	%	$	863,372		10.00	%
Tier 1 Capital to Risk-Weighted Assets:
Consolidated	$	1,601,361		18.50	%	$	735,752		8.50	%	$	519,354		6.00	%
First Financial Bank, N.A	$	1,421,727		16.47	%	$	733,866		8.50	%	$	690,698		8.00	%
Common Equity Tier 1 Capital to Risk-Weighted Assets:
Consolidated	$	1,601,361		18.50	%	$	605,913		7.00	%		—	N/A
First Financial Bank, N.A	$	1,421,727		16.47	%	$	604,361		7.00	%	$	561,192		6.50	%
Leverage Ratio:
Consolidated	$	1,601,361		12.06	%	$	346,236		4.00	%		—	N/A
First Financial Bank, N.A	$	1,421,727		10.75	%	$	345,349		4.00	%	$	431,686		5.00	%

	Actual					Minimum Capital Required-Basel III Fully Phased-In*					Required to be Considered Well- Capitalized
As of December 31, 2022:	Amount		Ratio			Amount		Ratio			Amount		Ratio
Total Capital to Risk-Weighted Assets:
Consolidated	$	1,586,888		19.29	%	$	863,622		10.50	%	$	822,497		10.00	%
First Financial Bank, N.A	$	1,442,902		17.58	%	$	861,860		10.50	%	$	820,819		10.00	%
Tier 1 Capital to Risk-Weighted Assets:
Consolidated	$	1,498,731		18.22	%	$	699,122		8.50	%	$	493,498		6.00	%
First Financial Bank, N.A	$	1,354,745		16.50	%	$	697,696		8.50	%	$	656,655		8.00	%
Common Equity Tier 1 Capital to Risk-Weighted Assets:
Consolidated	$	1,498,731		18.22	%	$	575,748		7.00	%		—	N/A
First Financial Bank, N.A	$	1,354,745		16.50	%	$	574,573		7.00	%	$	533,532		6.50	%
Leverage Ratio:
Consolidated	$	1,498,731		10.96	%	$	546,983		4.00	%		—	N/A
First Financial Bank, N.A	$	1,354,745		9.95	%	$	544,886		4.00	%	$	681,107		5.00	%