Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Summary of Significant Accounting Policies
Number of offices for delivery of banking, investment and trust services	75cyn_NumberOfOffices
Number of investment advisory affiliates	4
Number of unconsolidated subsidiary	1cyn_NumberOfUnconsolidatedSubsidiary
Percentage of assets acquired and liabilities assumed	100.00%
Loans
Past due period of interest or principal of loans excluding residential mortgage loans home equity loans and lines of credit placed on nonaccrual status	90 days
Past due period of interest or principal of residential mortgage loans home equity loans and lines of credit placed on nonaccrual status	180 days
Impaired Loans
Minimum limit for measuring impairment at the relationship level for borrowers with multiple loans exceeding $1,000,000	1,000,000
Acquired Impaired Loans
Allowance for loan losses, loans acquired	0
Allowance for Loan and Lease Losses and Reserve for Off-Balance Sheet Credit Commitments
Charge off of consumer loans, delinquency period for overdrafts, low end of range	60 days
Charge off of consumer loans, delinquency period for secured consumer loans	180 days
Software \| Minimum
Premises and Equipment
Estimated useful life of the software	3 years	5 years
Software \| Maximum
Premises and Equipment
Estimated useful life of the software	10 years	10 years

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Percentage of assets acquired and liabilities assumed in a business combination.

+ References

No definition available.

+ Details

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- Definition

Represents the minimum limit for aggregation of impaired loans for the purpose of measuring impairment using historical loss factors as a means of measurement which is applied at the total relationship level in cases where borrowers have multiple loans in excess of the individual limit.

+ References

No definition available.

+ Details

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- Definition

Represents the number of consolidated investment advisory affiliates.

+ References

No definition available.

+ Details

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- Definition

Represents the number of offices in different locations through which the entity carries out its operations.

+ References

No definition available.

+ Details

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- Definition

Represents the number of unconsolidated subsidiary of the entity.

+ References

No definition available.

+ Details

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- Definition

Represents the number of days contractually past with respect to interest or principal for loans with the exception of residential mortgage loans home equity loans and lines of credit that are placed on nonaccrual status.

+ References

No definition available.

+ Details

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- Definition

Represents the number of days contractually past with respect to interest or principal for residential mortgage loans home equity loans and lines of credit that are placed on nonaccrual status.

+ References

No definition available.

+ Details

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- Definition

Represents the low end of range for the charge off of consumer loans, which is the delinquency period for overdrafts.

+ References

No definition available.

+ Details

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- Definition

Represents the high end of range for the charge off of consumer loans, which is the delinquency period for secured consumer loans.

+ References

No definition available.

+ Details

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- Definition

Amount of addition to allowance reserve for credit loss arising from purchase of loan and lease portfolios.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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