Share-Based Compensation (Details) (USD $)	12 Months Ended
Dec. 31, 2013 plan	Dec. 31, 2012	Dec. 31, 2011
Share-Based Compensation
Number of share-based compensation plans	1
Shares available for future grants	3,300,000
Compensation cost recognized for share-based awards	$ 22,800,000	$ 18,600,000	$ 19,500,000
Total income tax benefit recognized for share-based compensation arrangements	9,500,000	7,800,000	8,100,000
Cash received from the exercise of stock options	40,466,000	22,428,000	5,089,000
Actual tax benefit realized for the tax deductions from stock option exercises	6,100,000	2,700,000
Amended and Restated City National Corporation 2008 Omnibus Plan
Share-based compensation
Granted (in shares)	0
Stock options
Share-based compensation, fair value
Weighted-average volatility (as a percent)	28.12%	30.55%	30.90%
Dividend yield (as a percent)	2.15%	2.14%	1.67%
Expected term	6 years 1 month 20 days	6 years 1 month 10 days	6 years 1 month 10 days
Risk-free interest rate (as a percent)	1.25%	1.43%	2.86%
Weighted-average grant-date fair values of options granted (in dollars per share)	$ 12.59	$ 11.63	$ 17.55
Total intrinsic value of options exercised	$ 14,800,000	$ 8,000,000	$ 2,800,000
Volatility look back period	20 years
Minimum vesting period	4 years
Expiration period	10 years
Restricted stock
Share-based compensation, fair value
Percentage of restricted stock vesting two years from the grant date	25.00%
Vesting period for first 25% of award from date of grant	2 years
Percentage of restricted stock vesting on each of the next three consecutive grant anniversary dates	25.00%
Restricted stock and restricted stock unit
Share-based compensation
Granted (in shares)	72,000
Share-based compensation, fair value
Minimum vesting period	5 years
Cash-settled restricted stock units
Share-based compensation
Granted (in shares)	92,000
Share-based compensation, fair value
Percentage of restricted stock vesting two years from the grant date	25.00%
Vesting period for first 25% of award from date of grant	2 years
Percentage of restricted stock vesting on each of the next three consecutive grant anniversary dates	25.00%

Represents the percent of the total restricted stock that in general vests two years from the date of grant.

No definition available.

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Represents the remaining percent of the total restricted stock that vests on each of the next three consecutive grant anniversary dates.

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No definition available.

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For the first 25% of the vesting award, description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

+ References

No definition available.

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The period over which the volatility is observed to estimate the volatility factor to be used in Black-Scholes valuation model.

+ References

No definition available.

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- Definition

The number of share-based compensation plans approved by the entity's shareholders.

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No definition available.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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-Glossary Financing Activities

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Weighted average expected volatility rate of share-based compensation awards.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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