Loans (Schedule Of Aging Of Loan Portfolio) (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	$ 11,951	$ 44,174
60-89 Days Past Due	17,333	30,426
Greater than 90 Days Past Due	13,053	5,006
Non-accrual Loans	192,714	242,319
Total Past Due	235,051	321,925
Loans Not Past Due	6,782,091	6,546,696
Loans and Leases Receivable, Gross, Carrying Amount	7,017,142	6,868,621
Commercial Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	337	7,037
60-89 Days Past Due	1,022	2,990
Non-accrual Loans	29,723	31,498
Total Past Due	31,082	41,525
Loans Not Past Due	1,789,977	1,399,642
Loans and Leases Receivable, Gross, Carrying Amount	1,821,059	1,441,167
Real Estate Construction Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due		14,634
60-89 Days Past Due		15,425
Greater than 90 Days Past Due		4,175
Non-accrual Loans	49,997	53,937
Total Past Due	49,997	88,171
Loans Not Past Due	199,006	321,815
Loans and Leases Receivable, Gross, Carrying Amount	249,003	409,986
Commercial Mortgage Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	10,366	12,569
60-89 Days Past Due	12,715	9,430
Greater than 90 Days Past Due	13,053	831
Non-accrual Loans	97,338	144,596
Total Past Due	133,472	167,426
Loans Not Past Due	3,615,052	3,772,635
Loans and Leases Receivable, Gross, Carrying Amount	3,748,524	3,940,061
Residential Mortgage And Equity Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	948	9,934
60-89 Days Past Due	3,596	2,581
Non-accrual Loans	15,656	12,288
Total Past Due	20,200	24,803
Loans Not Past Due	1,162,511	1,036,527
Loans and Leases Receivable, Gross, Carrying Amount	1,182,711	1,061,330
Installment And Other Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	300
Total Past Due	300
Loans Not Past Due	15,545	16,077
Loans and Leases Receivable, Gross, Carrying Amount	$ 15,845	$ 16,077

Financing Receivable Recorded Investment Not In Past Due

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- Definition

Financing receivables that are less than 60 days past due but more than 29 days past due.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

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Financing receivables that are less than 90 days past due but more than 59 days past due.

+ References

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- Definition

Financing receivables that are equal to or greater than 90 days past due.

+ References

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5111-111524

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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

+ References

Reference 1: 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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

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