Loans, Past Due (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Financing Receivable, Recorded Investment, Aging [Abstract]
Accruing Loans 30 to 89 Days Past Dues	$ 7,652cban_AccruingLoans30To89DaysPastDues	$ 9,701cban_AccruingLoans30To89DaysPastDues
Accruing Loans 90 Days or More Past Due	8	7
Total Accruing Loans Past Due	7,660	9,708
Nonaccrual Loans	14,779	18,334
Current Loans	731,195	718,052
Total Loans	753,634	746,094	738,194
Commercial [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Accruing Loans 30 to 89 Days Past Dues	484	872
Accruing Loans 90 Days or More Past Due	0	0
Total Accruing Loans Past Due	484	872
Nonaccrual Loans	558	405
Current Loans	50,732	49,683
Total Loans	51,774	50,960	43,979
Agricultural [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Accruing Loans 30 to 89 Days Past Dues	77	0
Accruing Loans 90 Days or More Past Due	0	0
Total Accruing Loans Past Due	77	0
Nonaccrual Loans	156	45
Current Loans	18,955	16,644
Total Loans	19,188	16,689	12,654
Commercial Construction [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Accruing Loans 30 to 89 Days Past Dues	383	142
Accruing Loans 90 Days or More Past Due	0	0
Total Accruing Loans Past Due	383	142
Nonaccrual Loans	3,223	3,251
Current Loans	45,005	47,866
Total Loans	48,611	51,259	54,608
Residential Construction [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Accruing Loans 30 to 89 Days Past Dues	105	0
Accruing Loans 90 Days or More Past Due	0	0
Total Accruing Loans Past Due	105	0
Nonaccrual Loans	0	0
Current Loans	9,925	11,221
Total Loans	10,030	11,221	9,779
Commercial [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Accruing Loans 30 to 89 Days Past Dues	1,754	2,309
Accruing Loans 90 Days or More Past Due	0	0
Total Accruing Loans Past Due	1,754	2,309
Nonaccrual Loans	5,018	5,325
Current Loans	335,073	324,597
Total Loans	341,845	332,231	337,835
Residential [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Accruing Loans 30 to 89 Days Past Dues	4,025	5,783
Accruing Loans 90 Days or More Past Due	0	0
Total Accruing Loans Past Due	4,025	5,783
Nonaccrual Loans	4,021	7,462
Current Loans	194,832	190,508
Total Loans	202,878	203,753	202,159
Farmland [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Accruing Loans 30 to 89 Days Past Dues	446	282
Accruing Loans 90 Days or More Past Due	0	0
Total Accruing Loans Past Due	446	282
Nonaccrual Loans	1,417	1,449
Current Loans	49,709	48,220
Total Loans	51,572	49,951	47,886
Consumer [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Accruing Loans 30 to 89 Days Past Dues	343	313
Accruing Loans 90 Days or More Past Due	8	7
Total Accruing Loans Past Due	351	320
Nonaccrual Loans	192	202
Current Loans	21,162	22,298
Total Loans	21,705	22,820	23,693
Other [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Accruing Loans 30 to 89 Days Past Dues	35	0
Accruing Loans 90 Days or More Past Due	0	0
Total Accruing Loans Past Due	35	0
Nonaccrual Loans	194	195
Current Loans	5,802	7,015
Total Loans	$ 6,031	$ 7,210	$ 5,601

Financing receivables that are less than 90 days past due but more than 29 days past due.

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Financing receivables that are current.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

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Financing receivables that are equal to or greater than 90 days past due.

+ References

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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