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Equity Incentive Plan - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	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	$ 819	$ 702	$ 617
Expected future compensation expense	$ 905
Weighted average remaining life of grants related to unvested awards not yet recognized	2 years 1 month 2 days
Civista Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common shares granted	8,098	8,792	14,266
Share based compensation - Civista BOD	$ 189	$ 196	$ 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
Number of shares available for grant under stock option plan	117,662
Options granted	0	0
Share based compensation expense	$ 630	$ 506	421
Expected future compensation expense	$ 905
Weighted average remaining life of grants related to unvested awards not yet recognized	2 years 1 month 2 days
2014 Incentive Plan [Member] \| Civista Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Director retainer fees	$ 189	$ 196	$ 196