Fair Value (Fair Value Of Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage loans held for sale	$ 11,110	$ 11,535
Impaired loans carried at fair value	83,324	87,813
Interest Rate Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	673	846
Fair Value Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	135	700
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	161,130	157,486
Investment securities	1,789,731	1,640,869
Accrued interest receivable		19,697
Mortgage loans held for sale	11,110	11,535
Impaired loans carried at fair value	83,324	87,813
Other loans	4,170,191	4,149,307
Loans receivable, net	4,264,625	4,248,655
Noninterest bearing checking accounts	1,055,745	995,733
Interest bearing transactions accounts	1,215,562	1,037,385
Savings accounts	1,001,789	931,526
Time deposits	1,541,374	1,499,105
Other	2,918	1,365
Total deposits	4,817,388	4,465,114
Short-term borrowings	236,687	263,594
Long-term debt	821,801	823,182
Subordinated debentures/notes	75,250	75,250
Accrued interest payable		4,916
Liabilities held for sale		536,186
Carrying Value [Member] \| Interest Rate Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	673	846
Carrying Value [Member] \| Fair Value Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	135	700
Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	161,130
Investment securities	1,417
Noninterest bearing checking accounts	1,055,745
Interest bearing transactions accounts	1,215,562
Savings accounts	1,001,789
Other	2,918
Total deposits	3,276,014
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	1,800,383
Mortgage loans held for sale	11,110
Loans receivable, net	11,110
Time deposits	1,547,748
Total deposits	1,547,748
Short-term borrowings	236,687
Long-term debt	907,995
Subordinated debentures/notes	68,475
Level 2 [Member] \| Interest Rate Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	673
Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	756
Impaired loans carried at fair value	83,324
Other loans	4,188,265
Loans receivable, net	4,271,589
Level 3 [Member] \| Fair Value Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	135
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	161,130	157,486
Investment securities	1,802,556	1,655,219
Accrued interest receivable		19,697
Mortgage loans held for sale	11,110	11,535
Impaired loans carried at fair value	83,324	87,813
Other loans	4,188,265	4,167,224
Loans receivable, net	4,282,699	4,266,572
Noninterest bearing checking accounts	1,055,745	995,733
Interest bearing transactions accounts	1,215,562	1,037,385
Savings accounts	1,001,789	931,526
Time deposits	1,547,748	1,506,075
Other	2,918	1,365
Total deposits	4,823,762	4,472,084
Short-term borrowings	236,687	263,594
Long-term debt	907,995	915,274
Subordinated debentures/notes	68,475	68,601
Accrued interest payable		4,916
Liabilities held for sale		536,991
Fair Value [Member] \| Interest Rate Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	673	846
Fair Value [Member] \| Fair Value Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	135	700
Securities [Member] \| Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	7,027
Securities [Member] \| Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	7,027
Securities [Member] \| Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	7,027
Loans [Member] \| Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	14,200
Loans [Member] \| Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	1
Loans [Member] \| Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	14,199
Loans [Member] \| Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	14,200
Deposits [Member] \| Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	2,824
Deposits [Member] \| Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	36
Deposits [Member] \| Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	2,788
Deposits [Member] \| Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	2,824
Debt/Borrowings [Member] \| Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	2,210
Debt/Borrowings [Member] \| Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	2,210
Debt/Borrowings [Member] \| Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	$ 2,210

Accrued Interest Receivable At Fair Value

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- Definition

Impaired Loan Fair Value

+ References

No definition available.

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- Definition

Interest Bearing Deposit Liabilities Fair Value

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- Definition

Interest Bearing Domestic Deposit Savings Fair Value

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No definition available.

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- Definition

Liabilities Held For Sale Fair Value Disclosure

+ References

No definition available.

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- Definition

Noninterest Bearing Deposit Liabilities Fair Value

+ References

No definition available.

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- Definition

Short Term Borrowings Fair Value

+ References

No definition available.

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- Definition

Time Deposits Fair Value

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No definition available.

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- Definition

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 8

-Footnote 2

-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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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 7, 8, 9, 10

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-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

Derivative instrument obligations meeting the definition of a liability which the Company is a party to as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 15

-Paragraph 83

-URI http://asc.fasb.org/extlink&oid=6913464&loc=d3e34841-113949

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 6

-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

Amount of subordinated debt obligations (also known as subordinated loan, subordinated bond, subordinated debenture or junior debt) which has a priority ranking after other debts in a dissolution, measured at fair value.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph a

-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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-Topic 820

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-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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- Definition

Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 14

-Paragraph 2, 3

-Article 12

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-SubTopic 320

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-Number 210

-Section 12

-Paragraph 3, 4

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- Definition

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

-URI http://asc.fasb.org/extlink&oid=6517073

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 114

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-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

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

+ References

No definition available.

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- Definition

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