Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Equity Incentive Plan - Additional Information (Detail) - USD ($) $ in Thousands			6 Months Ended
	May 21, 2020	May 21, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected future compensation expense			$ 849
Weighted average remaining life of grants related to unvested awards not yet recognized			2 years 9 months 18 days
Civista Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common shares granted	14,266	8,946
Share based compensation - Civista BOD	$ 196	$ 196
Restricted Stock [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares vesting service period			3 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			198,756
Options granted			0	0
Share based compensation expense			$ 223
Expected future compensation expense			$ 849
Weighted average remaining life of grants related to unvested awards not yet recognized			2 years 9 months 18 days
2014 Incentive Plan [Member] \| Civista Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation - Civista BOD			$ 196