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.

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- Definition

Payments for stock options exercised by holders.

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- Definition

Percentage of average total shareholder annual return necessary for vesting of share based payment award.

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No definition available.

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- Definition

The percentage of capped total shareholder return under share based payment arrangement.

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No definition available.

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- Definition

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

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- Definition

The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

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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.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

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No definition available.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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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

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Number of shares issued which are neither cancelled nor held in the treasury.

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No definition available.

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- Definition

Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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- Definition

Number of share options (or share units) exercised during the current period.

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Note 14 - Employee Benefits (Details Textual) - USD ($)		12 Months Ended
Note 14 - Employee Benefits (Details Textual) - USD ($)	May 10, 2017	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2007
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value			$ 166,759
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares)		12,150	2,350
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Average Total Shareholder Annual Return, Percentage		10.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Capped Total Shareholder Annual Return, Percentage		125.00%
Deferred Compensation Share-based Arrangements, Liability, Current and Noncurrent		$ 979,000	$ 581,000
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Average Total Shareholder Annual Return, Percentage		0.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Average Total Shareholder Annual Return, Percentage		10.00%
Share-based Payment Arrangement, Option [Member]
Payments For Stock Options Exercised		$ 21,000	$ 18,000
Restricted Stock [Member]
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture, Total (in shares)		29,193	23,648
Share-based Payment Arrangement, Expense		$ 478,000	$ 271,000
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount		$ 557,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		1 year 8 months 8 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value		$ 447,000	208,000
Retirement Plan [Member]
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 (Year)		6 years
Defined Benefit Plan, Plan Assets, Contributions by Employer		$ 347,000	350,000
Retirement Plan [Member] \| Middlefield Banking Company [Member]
Defined Contribution Plan Annual Vesting Percentage		20.00%
Retirement Plan [Member] \| Liberty Bank, N.A. [Member]
Deferred Compensation Arrangement with Individual, Requisite Service Period (Year)		3 years
Executive Deferred Compensation Plan [Member] \| Middlefield Banking Company [Member]
Deferred Compensation Arrangement with Individual, Recorded Liability		$ 1,900,000	1,700,000
Defined Contribution Plan, Employer Discretionary Contribution Amount		$ 264,000	$ 240,000
Stock Option and Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)				320,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term (Year)				10 years
Shares, Outstanding, Ending Balance (in shares)		0
The 2017 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)	448,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term (Year)	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)		386,188