Regulatory Requirements And Capital Ratios (Schedule Of Capital Amounts And Ratios) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital, Amount	$ 353,873us-gaap_Capital	$ 346,039us-gaap_Capital
Total Capital, Ratio	14.20%us-gaap_CapitalToRiskWeightedAssets	13.80%us-gaap_CapitalToRiskWeightedAssets
Total Capital, Well Capitalized Ratio	10.00%	10.00%
Total Capital, Minimum Ratio	8.00%	8.00%
Tier I Capital, Amount	333,163us-gaap_TierOneRiskBasedCapital	324,859us-gaap_TierOneRiskBasedCapital
Tier I Capital, Ratio	13.40%	13.00%
Tier I Capital, Well Capitalized Ratio	6.00%	6.00%
Tier I Capital, Minimum Ratio	4.00%	4.00%
Tier 1 Capital, Average Assets, Amount	333,163us-gaap_TierOneLeverageCapital	324,859us-gaap_TierOneLeverageCapital
Tier I Capital, Average Assets, Ratio	9.90%	9.80%
Tier 1 Capital, Average Assets, Well Capitalized Ratio	5.00%	5.00%
Tier I Capital, Average Assets, Minimum Ratio	4.00%	4.00%
City National
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital, Amount	315,095	302,817
Total Capital, Ratio	12.70%	12.20%
Total Capital, Well Capitalized Ratio	10.00%	10.00%
Total Capital, Minimum Ratio	8.00%	8.00%
Tier I Capital, Amount	294,870	282,221
Tier I Capital, Ratio	11.90%	11.40%
Tier I Capital, Well Capitalized Ratio	6.00%	6.00%
Tier I Capital, Minimum Ratio	4.00%	4.00%
Tier 1 Capital, Average Assets, Amount	$ 294,870	$ 282,221
Tier I Capital, Average Assets, Ratio	8.80%	8.60%
Tier 1 Capital, Average Assets, Well Capitalized Ratio	5.00%	5.00%
Tier I Capital, Average Assets, Minimum Ratio	4.00%	4.00%

The amount of total capital as defined in the regulations.

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

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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