Supplemental Cash Flow Information (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash payments [Abstract]
Interest Expense	$ 7,898,543cban_SupplementalInterestExpense	$ 7,111,361cban_SupplementalInterestExpense	$ 10,942,113cban_SupplementalInterestExpense
Income Taxes	113,000us-gaap_IncomeTaxesPaid	173,883us-gaap_IncomeTaxesPaid	0us-gaap_IncomeTaxesPaid
Noncash financing and investing activities [Abstract]
Acquisitions of Real Estate Through Loan Foreclosures	3,852,848us-gaap_FairValueOfAssetsAcquired	10,251,006us-gaap_FairValueOfAssetsAcquired	9,729,174us-gaap_FairValueOfAssetsAcquired
Change In Unrealized Gain (Loss) on AFS Investment Securities	$ 6,409,171	$ (13,523,050)	$ (3,120,540)

The amount of cash paid for interest during the period that includes the change in interest payable within the statement of cash flow.

No definition available.

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Period Type:	duration

- Definition

The fair value of assets acquired in noncash investing or financing activities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

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- Details

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- Definition

The value of the noncash (or part noncash) consideration received in a transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of a transaction not resulting in cash receipts or cash payments in the period.

+ References

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