Share-Based Compensation (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014 plan	Jun. 30, 2013	Jun. 30, 2014 plan	Jun. 30, 2013
Share-Based Compensation
Number of share-based compensation plans	1		1
Shares available for future grants	2,800,000		2,800,000
Compensation cost recognized for share-based awards	$ 5,200,000	$ 5,400,000	$ 10,600,000	$ 10,500,000
Total income tax benefit recognized for share-based compensation arrangements	2,200,000	2,300,000	4,500,000	4,400,000
Cash received from the exercise of stock options			16,387,000	17,838,000
Actual tax benefit realized for the tax deductions from stock option exercises			2,200,000	3,500,000
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)	27.15%		27.35%	28.12%
Dividend yield (as a percent)	1.78%		1.79%	2.15%
Expected term	5 years 5 months 16 days		6 years 22 days	6 years 1 month 24 days
Risk-free interest rate (as a percent)	1.92%		1.99%	1.24%
Weighted-average grant-date fair values of options granted (in dollars per share)			$ 17.93	$ 12.57
Total intrinsic value of options exercised			$ 5,200,000	$ 8,500,000