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Equity Incentive Plan - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected future compensation expense	$ 1,231		$ 1,231
Weighted average remaining life of grants related to unvested awards not yet recognized			2 years 7 months 9 days
Civista Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common shares granted			7,224
Share based compensation - Civista BOD			$ 168
Restricted Stock [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares vesting service period			3 years
Restricted Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares vesting service period			5 years
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	117,263		117,263
Options granted			0	0
Share based compensation expense	$ 153	$ 135	$ 331	$ 260
Expected future compensation expense	$ 1,231		$ 1,231
Weighted average remaining life of grants related to unvested awards not yet recognized			2 years 7 months 9 days
2014 Incentive Plan [Member] \| Civista Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Director retainer fees			$ 168