Defined Contribution Plan Annual Vesting Percentage

No definition available.

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- Details

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- Definition

Postretirement benefits percentage of compensation.

+ References

No definition available.

+ Details

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- Definition

Retirement Benefits Term

+ References

No definition available.

+ Details

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- Definition

The minimum period that the individual is required to perform services in order to be fully vested under the deferred compensation arrangement.

+ 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 (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Maximum percentage of employee gross pay the employee may contribute 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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Period Type:	duration

- 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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.D.2)

-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

+ 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Note 13 - Employee Benefits (Details) (USD $)	12 Months Ended
Note 13 - Employee Benefits (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Note 13 - Employee Benefits (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term			9 years 350 days
Maximum Matching Contribution [Member] \| Retirement Plan [Member]
Note 13 - Employee Benefits (Details) [Line Items]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	6.00%
Middlefield Banking Company [Member] \| Retirement Plan [Member]
Note 13 - Employee Benefits (Details) [Line Items]
Defined Contribution Plan Annual Vesting Percentage	20.00%
Middlefield Banking Company [Member] \| Directors Retirement Plan [Member]
Note 13 - Employee Benefits (Details) [Line Items]
Deferred Compensation Arrangement with Individual, Requisite Service Period	five
Retirement Benefits Term	10 years
Postretirement Benefits Percentage of Compensation	25.00%
Middlefield Banking Company [Member] \| Executive Deferred Compensation Plan [Member]
Note 13 - Employee Benefits (Details) [Line Items]
Defined Contribution Plan, Employer Discretionary Contribution Amount (in Dollars)	$ 120,000	$ 139,000	$ 91,000
Emerald Bank [Member] \| Retirement Plan [Member] \| After One Year of Employment [Member]
Note 13 - Employee Benefits (Details) [Line Items]
Defined Contribution Plan Annual Vesting Percentage	50.00%
Emerald Bank [Member] \| Retirement Plan [Member] \| After Two Years of Employment [Member]
Note 13 - Employee Benefits (Details) [Line Items]
Defined Contribution Plan Annual Vesting Percentage	75.00%
Retirement Plan [Member]
Note 13 - Employee Benefits (Details) [Line Items]
Deferred Compensation Arrangement with Individual, Requisite Service Period	one
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	50.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	6 years
Defined Benefit Plan, Contributions by Employer (in Dollars)	$ 155,000	$ 125,000	$ 104,000
Retirement Plan [Member] \| Less Than One Year of Employment [Member]
Note 13 - Employee Benefits (Details) [Line Items]
Defined Contribution Plan Annual Vesting Percentage	25.00%
Stock Option and Restricted Stock Plan [Member]
Note 13 - Employee Benefits (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)	160,000
Stock Option and Restricted Stock Plan [Member] \| Maximum [Member]
Note 13 - Employee Benefits (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	10 years
Omnibus Equity Plan [Member]
Note 13 - Employee Benefits (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	0	1,722	2,400