Summary Of Significant Accounting And Reporting Policies (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Other Real Estate, Foreclosed Assets, and Repossessed Assets	$ 8.2	$ 8.5
Amount of tax benefit that is greater than	50.00%
Investments in affordable housing limited partnerships	0.9	1.3
Cash paid for interest	12.1us-gaap_InterestPaid	13.4us-gaap_InterestPaid	14.9us-gaap_InterestPaid
Income taxes paid	23.0us-gaap_IncomeTaxesPaid	16.6us-gaap_IncomeTaxesPaid	14.7us-gaap_IncomeTaxesPaid
Held-to-maturity Securities, Transferred Security, at Carrying Value				$ 83.4
City National
Condensed Financial Statements, Captions [Line Items]
Number of offices	82

Investment In Affordable Housing Limited Partnerships

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Uncertain Tax Position Initially Recognized At Tax Benefit Minimum Threshold

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For any transfer of securities categorized as held-to-maturity, this item represents the net carrying amount of the transferred security to another category of investments in debt and equity securities (trading or available-for-sale).

+ References

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-Name Accounting Standards Codification

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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-Publisher FASB

-Name Accounting Standards Codification

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The amount of cash paid for interest during the period.

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Represents the number of stores.

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Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

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-Topic 942

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-Subparagraph (SX 210.9-03.10(4))

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