Earnings per Common Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013		Jun. 30, 2012
Basic EPS:
Net income attributable to City National Corporation	$ 59,741	$ 54,758	$ 111,264	[1]	$ 101,023	[1]
Less: Dividends on preferred stock	2,406		4,812
Net income available to common shareholders	57,335	54,758	106,452		101,023
Less: Earnings allocated to participating securities	656	788	1,287		1,532
Earnings allocated to common shareholders	56,679	53,970	105,165		99,491
Weighted average common shares outstanding	54,105,000	53,105,000	53,919,000		52,923,000
Basic earnings per common share (in dollars per share)	$ 1.05	$ 1.02	$ 1.95		$ 1.88
Diluted EPS:
Earnings allocated to common shareholders	$ 56,682	$ 53,972	$ 105,173		$ 99,496
Weighted average common shares outstanding	54,105,000	53,105,000	53,919,000		52,923,000
Dilutive effect of equity awards (in shares)	372,000	268,000	361,000		294,000
Weighted average diluted common shares outstanding	54,477,000	53,373,000	54,280,000		53,217,000
Diluted earnings per common share (in dollars per share)	$ 1.04	$ 1.01	$ 1.94		$ 1.87
Average outstanding stock options
Antidilutive securities not included in calculation of diluted EPS:
Antidilutive securities not included in calculation of diluted EPS (in shares)	2,400,000	2,700,000	2,300,000		2,800,000

[1] Net income excludes net income attributable to redeemable noncontrolling interest of $1,048 and $652 for the six month periods ended June 30, 2013 and 2012, respectively. Redeemable noncontrolling interest is reflected in the mezzanine section of the consolidated balance sheets. See Note 18 of the Notes to the Unaudited Consolidated Financial Statements.