Minimum percentage of the total merger consideration that will be paid in company stock.

No definition available.

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Period Type:	instant

- Definition

Represents the number of shares of the acquiring entity into which the shares of the acquired entity may be converted pursuant to a definitive agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	cban_
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Balance Type:	na
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- Definition

Percentage of shares being acquired that will receive cash consideration.

+ References

No definition available.

+ Details

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Namespace Prefix:	cban_
Data Type:	num:percentItemType
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- Definition

Percentage of shares being acquired that will receive stock consideration.

+ References

No definition available.

+ Details

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Namespace Prefix:	cban_
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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

+ Details

Name:	us-gaap_BusinessAcquisitionSharePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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Balance Type:	credit
Period Type:	duration

- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	duration

- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 20
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-SubTopic 20
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-Paragraph 1
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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-Paragraph 5
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-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

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Period Type:	instant

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
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-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

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Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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Balance Type:
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- Details

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Note 2 - Business Acquisition (Details Textual) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended
	May 01, 2019	Apr. 16, 2019	Oct. 22, 2018	Mar. 31, 2019	Dec. 31, 2018
Goodwill, Ending Balance				$ 202	$ 202
Assets, Total				1,279,077	1,251,878
Deposits, Total				1,111,678	$ 1,085,125
LBC Bancshares, Inc [Member]
Assets, Total				207,300
Financing Receivable, after Allowance for Credit Loss, Total				131,900
Deposits, Total				184,900
Planters First Bank [Member]
Payments to Acquire Businesses, Gross			$ 10,238
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual				71
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual				$ (75)
Goodwill, Ending Balance			202
Business Acquisition, Goodwill, Expected Tax Deductible Amount			202
Business Combination, Consideration Transferred, Total			$ 10,238
LBC Bancshares, Inc [Member] \| Subsequent Event [Member]
Payments to Acquire Businesses, Gross	$ 15,300
Business Acquisition, Share Price	$ 23.50
Business Acquisition, Number of Shares of Acquiring Entity for Each Share of Acquired Entity	1.3239
Business Acquistion, Percentage of Shares Receiving Stock Consideration	55.00%
Business Acquistion, Percentage of Shares Receiving Cash Consideration	45.00%
Business Acquisition, Minimum Percentage of Merger Consideration Paid in Stock	50.00%
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	1,054,029
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	$ 18,700
PFB Mortgage [Member] \| Subsequent Event [Member]
Business Combination, Consideration Transferred, Total		$ 833