Deposits (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Deposits [Abstract]
Aggregate amount of overdrawn deposit accounts reclassified as loan balances	$ 511,387cban_TotalAmountOfOverdrawnDeposit	$ 400,552cban_TotalAmountOfOverdrawnDeposit
Components of interest-bearing deposits [Abstract]
Interest-Bearing Demand	363,501,727us-gaap_DemandDepositAccounts	357,290,975us-gaap_DemandDepositAccounts
Savings	59,215,257us-gaap_DepositsSavingsDeposits	54,094,617us-gaap_DepositsSavingsDeposits
Time, $100,000 and Over	210,502,901us-gaap_TimeDeposits100000OrMore	220,672,794us-gaap_TimeDeposits100000OrMore
Other Time	217,743,826us-gaap_TimeDepositsLessThan100000	240,210,393us-gaap_TimeDepositsLessThan100000
Total Interest bearing Deposits	850,963,711	872,268,779
Brokered deposits balances	26,298,267	26,579,934
Certificates of deposits, $100,000 or more	140,832,026cban_CertificatesOfDeposits100000OrMore	148,388,694cban_CertificatesOfDeposits100000OrMore
Scheduled maturities of certificates of deposits [Abstract]
2015	302,584,884us-gaap_TimeDepositMaturitiesYearOne
2016	72,869,687us-gaap_TimeDepositMaturitiesYearTwo
2017	25,349,468us-gaap_TimeDepositMaturitiesYearThree
2018	19,773,611us-gaap_TimeDepositMaturitiesYearFour
2019 and Thereafter	7,669,077
Total	$ 428,246,727us-gaap_TimeDeposits

The aggregate amount of domestic and foreign certificates of deposit liabilities in denominations of $100,000 or more.

No definition available.

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- Definition

Amount of time deposits maturing in the fifth fiscal year following the latest fiscal year and in years after the fifth fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Refers to the aggregate amount of overdrawn deposit accounts reclassified as loan balances as of balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The amount of money in accounts that may bear interest and that the depositor is entitled to withdraw at any time without prior notice.

+ References

+ Details

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- Details

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- Definition

Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

+ References

+ Details

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- Definition

The aggregate of all domestic and foreign interest-bearing deposit liabilities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.12)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 9

+ Details

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- Definition

Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities.

+ References

+ Details

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- Definition

Amount of time deposits maturing in the fourth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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- Definition

Amount of time deposits maturing in the next fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of time deposits maturing in the third fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of time deposits maturing in the second fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

+ References

+ Details

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- Definition

The aggregate amount of domestic and foreign time deposit liabilities (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 405

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6479006&loc=d3e64164-112818

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

-Publisher SEC

-Name Industry Guide

-Number 3

-Section V

-Paragraph A

-Subparagraph 4

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- Definition

The aggregate amount of domestic or foreign time deposits (including certificates of deposits, individual retirement accounts and open accounts) that total to less than $100,000.

+ References

No definition available.

+ Details

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