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Equity Incentive Plan - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Feb. 20, 2024	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares vesting service period	3 years
Share based compensation - Civista BOD	$ 871	$ 984	$ 819
Expected future compensation expense	$ 1,052
Weighted average remaining life of grants related to unvested awards not yet recognized	2 years 4 months 2 days
Civista Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common shares granted	10,626	11,817	8,098
Share based compensation - Civista BOD	$ 154	$ 189	$ 196
2014 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares under stock option plan authorized for issuance					375,000
Plan expiration date	Apr. 16, 2024
Number of shares available for grant under stock option plan	438,087
Options granted	0	0
Share based compensation expense	$ 718	$ 801	$ 630
Expected future compensation expense	$ 1,052
Weighted average remaining life of grants related to unvested awards not yet recognized	2 years 4 months 2 days
2024 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares under stock option plan authorized for issuance				450,000
Options granted	0	0