Short-Term Debt (Summary Of Short-Term Borrowings) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Short-term Debt [Abstract]
Short-term borrowings	$ 134,931chco_CustomerRepurchaseAgreements	$ 137,798chco_CustomerRepurchaseAgreements	$ 114,646chco_CustomerRepurchaseAgreements
Customer repurchase agreements, avg outstanding	133,769	127,616	121,270
Federal Funds purchased, avg outstanding		63	510
Customer repurchase agreements, Max. outstanding at any month end	$ 151,637	$ 150,943	$ 131,971
Customer repurchase agreements, Weighted-averaged interest rate, During the year	0.26%	0.25%	0.26%
Federal Funds purchased, Weighted-averaged interest rate, During the year		0.31%	0.28%
Customer repurchase agreements, Weighted-average interest rate, End of the year	0.26%	0.25%	0.26%
Federal Funds purchased, Weighted-average interest rate, End of the year		0.31%	0.28%

Customer repurchase agreements

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Federal Funds Purchased Activity For Year Average Balance Of Agreements Outstanding

No definition available.

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Federal Funds Purchased Activity For Year Average Interest Rate At Period End

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Federal Funds Purchased Activity For Year Average Interest Rate For Year

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Securities Sold Under Agreements To Repurchase Activity For Year Average Balance Of Agreements Outstanding

No definition available.

Name:	chco_SecuritiesSoldUnderAgreementsToRepurchaseActivityForYearAverageBalanceOfAgreementsOutstanding
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Securities Sold Under Agreements To Repurchase Activity For Year Average Interest Rate At Period End

No definition available.

Name:	chco_SecuritiesSoldUnderAgreementsToRepurchaseActivityForYearAverageInterestRateAtPeriodEnd
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Securities Sold Under Agreements To Repurchase Activity For Year Average Interest Rate For Year

No definition available.

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Securities Sold Under Agreements To Repurchase Activity For Year Maximum Outstanding At Any Month End

No definition available.

Name:	chco_SecuritiesSoldUnderAgreementsToRepurchaseActivityForYearMaximumOutstandingAtAnyMonthEnd
Namespace Prefix:	chco_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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