Loans And Allowance For Loan Losses (Summary Of Individual And Collective Allowance For Loan Losses And Loan Balances By Class) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2012	Dec. 31, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Individually Evaluated for Impairment	$ 6,082	$ 7,147
Allowance, Collectively Evaluated for Impairment	96,011	93,515
Allowance, Purchased Credit- Impaired Loans
Loans Outstanding	7,802,792	6,856,667
Loans Outstanding, Individually Evaluated for Impairment	85,470	83,504
Loans Outstanding, Collectively Evaluated for Impairment	7,698,115	6,757,324
Loans Outstanding, Purchased Credit-Impaired Loans	19,207	15,839
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Individually Evaluated for Impairment	2,137	2,482
Allowance, Collectively Evaluated for Impairment	29,305	27,855
Allowance, Purchased Credit- Impaired Loans
Loans Outstanding	2,521,571	2,341,646
Loans Outstanding, Individually Evaluated for Impairment	38,086	36,566
Loans Outstanding, Collectively Evaluated for Impairment	2,464,278	2,289,241
Loans Outstanding, Purchased Credit-Impaired Loans	19,207	15,839
Commercial Real Estate - FL [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Individually Evaluated for Impairment	3,389	2,389
Allowance, Collectively Evaluated for Impairment	9,566	10,557
Allowance, Purchased Credit- Impaired Loans
Loans Outstanding	135,547	154,081
Loans Outstanding, Individually Evaluated for Impairment	39,021	39,122
Loans Outstanding, Collectively Evaluated for Impairment	96,526	114,959
Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Individually Evaluated for Impairment	556	2,276
Allowance, Collectively Evaluated for Impairment	26,318	23,200
Allowance, Purchased Credit- Impaired Loans
Loans Outstanding	1,451,144	1,363,692
Loans Outstanding, Individually Evaluated for Impairment	8,363	7,816
Loans Outstanding, Collectively Evaluated for Impairment	1,442,781	1,355,876
Commercial Leases [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Collectively Evaluated for Impairment	1,669	1,556
Allowance, Purchased Credit- Impaired Loans
Loans Outstanding	118,050	110,795
Loans Outstanding, Collectively Evaluated for Impairment	118,050	110,795
Total Commercial Loans And Leases [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Individually Evaluated for Impairment	6,082	7,147
Allowance, Collectively Evaluated for Impairment	66,858	63,168
Allowance, Purchased Credit- Impaired Loans
Loans Outstanding	4,226,312	3,970,214
Loans Outstanding, Individually Evaluated for Impairment	85,470	83,504
Loans Outstanding, Collectively Evaluated for Impairment	4,122,635	3,870,871
Loans Outstanding, Purchased Credit-Impaired Loans	19,207	15,839
Direct Installment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Collectively Evaluated for Impairment	13,750	14,814
Allowance, Purchased Credit- Impaired Loans
Loans Outstanding	1,082,964	1,029,187
Loans Outstanding, Collectively Evaluated for Impairment	1,082,964	1,029,187
Residential Mortgages [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Collectively Evaluated for Impairment	4,499	4,437
Allowance, Purchased Credit- Impaired Loans
Loans Outstanding	1,187,448	670,936
Loans Outstanding, Collectively Evaluated for Impairment	1,187,448	670,936
Indirect Installment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Collectively Evaluated for Impairment	5,385	5,503
Allowance, Purchased Credit- Impaired Loans
Loans Outstanding	563,929	540,789
Loans Outstanding, Collectively Evaluated for Impairment	563,929	540,789
Consumer Lines Of Credit [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Collectively Evaluated for Impairment	5,361	5,447
Allowance, Purchased Credit- Impaired Loans
Loans Outstanding	704,773	607,280
Loans Outstanding, Collectively Evaluated for Impairment	704,773	607,280
Other [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Collectively Evaluated for Impairment	158	146
Allowance, Purchased Credit- Impaired Loans
Loans Outstanding	37,366	38,261
Loans Outstanding, Collectively Evaluated for Impairment	$ 37,366	$ 38,261

Allowance for purchased impaired loans.

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524

-Subparagraph (g)

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

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- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 114

-Paragraph 20

-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Subsection I

-Paragraph 8

-Subparagraph j(ii)

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 15

-Paragraph 40

-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.

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- Definition

Reflects the aggregate gross carrying amount of all categories of loans and leases held in portfolio, after deducting deferred income, but before deducting the allowance for losses on loans and leases.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5074-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6375948&loc=d3e4428-111522

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph e

-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.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Chapter 8

-Paragraph 116

-IssueDate 2006-05-01

-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.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 8

-Subparagraph e

-Subsection I

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

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