Represents a percentage of the available-for-sale securities portfolio.

No definition available.

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5086-111524

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
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- Definition

In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

+ References

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-Publisher FASB
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- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
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- Details

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- Details

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Note 6 - Investment Securities Available for Sale (Details Textual) - USD ($)	3 Months Ended	6 Months Ended
	Mar. 31, 2017	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016
Available-for-sale Securities Pledged as Collateral		$ 59,300,000	$ 60,300,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions		27
Available-for-sale Securities, Percentage of Portfolio		100.00%
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held		$ 0		$ 0
Merger of Liberty Bank, N.A. into The Middlefield Banking Company [Member]
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain	$ 488,000	488,000
Pledged to Secure Deposits and Other Purposes Required by Law [Member]
Restricted Cash		$ 4,500,000