Acquisition And Divestiture Activity (Schedule Of Components Of Estimated Fair Value Of Intangible Assets) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2012
Core Deposit Intangible [Member]
Estimated Fair Value	$ 8.2
Estimated Useful Lives (Years)	10 years
Trust Customer Relationship Intangible [Member]
Estimated Fair Value	$ 2.3
Estimated Useful Lives (Years)	12 years

This element represents the sum of all intangible assets having statutory or estimated useful lives.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 33

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Name:	us-gaap_FiniteLivedIntangibleAssetsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant