Derivative Interest Rate Floors Matured

No definition available.

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- Definition

Derivative Interest Rate Floors Notional Value Sold

+ References

No definition available.

+ Details

Name:	chco_DerivativeInterestRateFloorsNotionalValueSold
Namespace Prefix:	chco_
Data Type:	xbrli:monetaryItemType
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- Definition

Increase in the fair value of the derivative or group of derivatives included in earnings in the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5618551-113959

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- Definition

High end of the range of variable interest rates when a range is presented for a group of interest rate derivatives.

+ References

No definition available.

+ Details

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- Details

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- Definition

Low end of the range of variable interest rates when a range is presented for a group of interest rate derivatives.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeLowerVariableInterestRateRange
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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

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- Definition

Aggregate notional amount of all interest rate derivatives designated as hedging instruments in cash flow hedges. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

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- Definition

Aggregate notional amount of interest rate derivatives, which relates to the currency amount specified in the interest rate derivative instruments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

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Derivative Instruments (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended	12 Months Ended		12 Months Ended
	Jun. 30, 2011	Dec. 31, 2008	Dec. 31, 2012 item	Dec. 31, 2012 Maximum [Member]	Dec. 31, 2012 Minimum [Member]
Derivative [Line Items]
Interest rate floors notional value			$ 600
Number of derivatives designaged as cash flow hedges			7
Notional amount of derivatives designated as cash flow hedges			500
Interest rate floors maturity date				Jun. 30, 2011	May 01, 2008
Strike rate, lower range			6.00%
Strike rate, higher range			8.00%
Interest rate floors matured		150
Notional value of interest rate floors sold		450
Gain on sale of derivatives	$ 16.8