Shares authorized to be repurchased as percentage of common stock outstanding.

No definition available.

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Namespace Prefix:	cldb_
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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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

- Definition

Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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

- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

+ Details

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

- Details

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- Details

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- Details

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Stock Repurchase Program (Details Textual) - USD ($)			3 Months Ended	12 Months Ended
Stock Repurchase Program (Details Textual) - USD ($)	Jan. 24, 2017	Jan. 26, 2016	Mar. 31, 2017	Dec. 31, 2016
Equity Class Of Treasury Stock [Line Items]
Common stock, shares outstanding			4,434,887	4,420,255
Stock Repurchase Program on January 26, 2016
Equity Class Of Treasury Stock [Line Items]
Percentage of shares authorized to be repurchased to common stock outstanding		2.30%
Common stock, shares outstanding		4,404,783
Stock repurchase program expiration date			Dec. 31, 2016
Stock repurchase program, shares repurchased				0
Stock Repurchase Program on January 26, 2016 \| Maximum
Equity Class Of Treasury Stock [Line Items]
Shares authorized to be repurchased		100,000
Stock Repurchase Program on January 24, 2017
Equity Class Of Treasury Stock [Line Items]
Percentage of shares authorized to be repurchased to common stock outstanding	2.30%
Common stock, shares outstanding	4,420,055
Stock repurchase program, authorized amount			$ 1,900,000
Stock repurchase program expiration date			Dec. 31, 2017
Stock repurchase program, shares repurchased			0
Stock Repurchase Program on January 24, 2017 \| Maximum
Equity Class Of Treasury Stock [Line Items]
Shares authorized to be repurchased	100,000