Income Taxes (Summary Of Deferred Tax Assets And Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Previously securitized loans	$ 4,703	$ 5,166
Allowance for loan losses	7,413	7,566
Deferred compensation payable	3,966	3,774
Underfunded pension liability	3,113	1,675
Accrued expenses	2,451chco_DeferredTaxAssetsAccruedExpenses	2,830chco_DeferredTaxAssetsAccruedExpenses
Impaired assets	1,172	1,028
Impaired security losses	8,377	9,519
Unrealized securities losses	0	1,230
Intangible assets	4,946chco_DeferredTaxAssetsIntangibleAssets	8,081chco_DeferredTaxAssetsIntangibleAssets
Other	3,292us-gaap_DeferredTaxAssetsOther	3,109us-gaap_DeferredTaxAssetsOther
Total Deferred Tax Assets	39,433us-gaap_DeferredTaxAssetsGross	43,978us-gaap_DeferredTaxAssetsGross
Unrealized securities gains	741	0
Other	1,926us-gaap_DeferredTaxLiabilitiesOther	1,813us-gaap_DeferredTaxLiabilitiesOther
Total Deferred Tax Liabilities	2,667us-gaap_DeferredTaxLiabilities	1,813us-gaap_DeferredTaxLiabilities
Net Deferred Tax Assets	$ 36,766us-gaap_DeferredTaxAssetsNet	$ 42,165us-gaap_DeferredTaxAssetsNet

Deferred Tax Assets Accrued Expenses

No definition available.

Name:	chco_DeferredTaxAssetsAccruedExpenses
Namespace Prefix:	chco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Deferred Tax Assets Allowance For Loan Losses

+ References

No definition available.

+ Details

Name:	chco_DeferredTaxAssetsAllowanceForLoanLosses
Namespace Prefix:	chco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Deferred Tax Assets Deferred Compensation Payable

+ References

No definition available.

+ Details

Name:	chco_DeferredTaxAssetsDeferredCompensationPayable
Namespace Prefix:	chco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Deferred Tax Assets Impaired Property Plant And Equipment

+ References

No definition available.

+ Details

Name:	chco_DeferredTaxAssetsImpairedPropertyPlantAndEquipment
Namespace Prefix:	chco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Deferred Tax Assets Impaired Security Losses

+ References

No definition available.

+ Details

Name:	chco_DeferredTaxAssetsImpairedSecurityLosses
Namespace Prefix:	chco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Deferred Tax Assets Intangible Assets

+ References

No definition available.

+ Details

Name:	chco_DeferredTaxAssetsIntangibleAssets
Namespace Prefix:	chco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Deferred Tax Assets Previously Securitized Loans

+ References

No definition available.

+ Details

Name:	chco_DeferredTaxAssetsPreviouslySecuritizedLoans
Namespace Prefix:	chco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Deferred Tax Assets Underfunded Pension Liability

+ References

No definition available.

+ Details

Name:	chco_DeferredTaxAssetsUnderfundedPensionLiability
Namespace Prefix:	chco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Deferred Tax Asset

-URI http://asc.fasb.org/extlink&oid=6510090

+ Details

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

- Definition

Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

+ References

+ Details

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

- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences not separately disclosed.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32621-109319

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 25

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=29652012&loc=d3e28680-109314

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32632-109319

+ Details

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

- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from unrealized losses on available-for-sale securities.

+ References

+ Details

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

- Definition

Amount of deferred tax liability attributable to taxable temporary differences net of deferred tax asset attributable to deductible temporary differences and carryforwards after valuation allowances.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=21917399&loc=d3e31931-109318

+ Details

Name:	us-gaap_DeferredTaxLiabilities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of deferred tax liability attributable to taxable temporary differences not separately disclosed.

+ References

+ Details

Name:	us-gaap_DeferredTaxLiabilitiesOther
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of deferred tax liability attributable to taxable temporary differences from unrealized gains on trading securities.

+ References

+ Details

Name:	us-gaap_DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_IncomeTaxDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration