Defined Contribution Plan Annual Vesting Percentage

No definition available.

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- Definition

The percentage of matching voluntary contributions that the bank bases its contributions to the plan on.

+ References

No definition available.

+ Details

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- Definition

Postretirement benefits percentage of compensation.

+ References

No definition available.

+ Details

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- Definition

The term for retirement benefits.

+ References

No definition available.

+ Details

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- Definition

Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, 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 710
-SubTopic 10
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6409961&loc=d3e20487-108367

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Amount of contributions made by the employer to defined benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
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+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

+ Details

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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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Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Expected term of share-based compensation awards, 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
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Note 14 - Employee Benefits (Details Textual) - USD ($)	12 Months Ended
Note 14 - Employee Benefits (Details Textual) - USD ($)	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Retirement Plan [Member]
Deferred Compensation Arrangement with Individual, Requisite Service Period	1 year
Defined Contribution Plan Employer Voluntary Matching Bank Contribution	50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	6.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	6 years
Defined Benefit Plan, Contributions by Employer	$ 156,000	$ 156,000	$ 143,000
Retirement Plan [Member] \| Middlefield Banking Company [Member]
Defined Contribution Plan Annual Vesting Percentage	20.00%
Directors Retirement Plan [Member] \| Middlefield Banking Company [Member]
Deferred Compensation Arrangement with Individual, Requisite Service Period	5 years
Retirement Benefits Term	10 years
Postretirement Benefits Percentage of Compensation	25.00%
Executive Deferred Compensation Plan [Member] \| Middlefield Banking Company [Member]
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 99,000	$ 65,000	$ 115,000
Stock Option and Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	160,000
Stock Option and Restricted Stock Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	10 years
Omnibus Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0	0