Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
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-Subparagraph (h)(1)(i)
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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
-Subparagraph (a)(1)
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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (c)(2)(iii)(2)
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Net number of share options (or share units) granted during the period.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
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- Definition

Percentage of vesting of share-based compensation awards.

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Equity Incentive Plan - Additional Information (Detail) - USD ($) $ in Thousands									12 Months Ended
	Nov. 03, 2016	Sep. 19, 2016	May 17, 2016	May 13, 2016	Mar. 11, 2016	Jan. 15, 2016	Jan. 04, 2016	Mar. 17, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common shares granted									28,864	16,983
Number of common Restricted Shares, Vested									5,657
Share based compensation - Civista BOD									$ 323	$ 106
Share based compensation expense									323
Expected future compensation expense									$ 89
Expected future compensation expense, restricted shares vesting period									4 years
Number of restricted shares, forfeited	1,558	916		666					3,140
Restricted Shares Awarded in 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common shares granted									16,983
Expected future compensation expense									$ 37
Expected future compensation expense, restricted shares vesting period									1 year
Restricted Shares Awarded in 2016 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common shares granted									16,130
Expected future compensation expense									$ 67
Expected future compensation expense, restricted shares vesting period									2 years
Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common shares granted									12,734
Civista [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation - Civista BOD			$ 130				$ 32
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares vesting service period					3 years				3 years
Restricted common shares granted			12,285				2,730	16,983
Number of common Restricted Shares, Vested								5,657
Restricted Stock [Member] \| Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common shares granted					16,130
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									317,280
Options granted									0	0
2014 Incentive Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares vesting service period						5 years
Restricted common shares granted						12,734
Vesting percentage of option grants in each year						20.00%