Securities (Schedule Of Amortized Cost And Fair Value Of Securities Held To Maturity) (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 984,201	$ 940,481
Gross Unrealized Gains	38,348	26,682
Gross Unrealized Losses	(1,906)	(7,749)
Held to Maturity, Fair Value, total	1,020,643	959,414
U.S. Treasury And Other U.S. Government Agencies And Corporations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	4,605	4,925
Gross Unrealized Gains	351	212
Held to Maturity, Fair Value, total	4,956	5,137
Agency Mortgage Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	739,501	688,575
Gross Unrealized Gains	31,714	23,878
Gross Unrealized Losses		(3,079)
Held to Maturity, Fair Value, total	771,215	709,374
Agency Collateralized Mortgage Obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	58,610	71,102
Gross Unrealized Gains	750	511
Gross Unrealized Losses	(172)	(889)
Held to Maturity, Fair Value, total	59,188	70,724
Non-Agency Collateralized Mortgage Obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	27,006	33,950
Gross Unrealized Gains	197	328
Gross Unrealized Losses	(1,135)	(1,331)
Held to Maturity, Fair Value, total	26,068	32,947
States Of The U.S. And Political Subdivisions [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	150,419	137,210
Gross Unrealized Gains	5,305	1,735
Gross Unrealized Losses	(6)	(1,630)
Held to Maturity, Fair Value, total	155,718	137,315
Collateralized Debt Obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	2,477	3,132
Gross Unrealized Losses	(434)	(778)
Held to Maturity, Fair Value, total	2,043	2,354
Other Debt Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	1,583	1,587
Gross Unrealized Gains	31	18
Gross Unrealized Losses	(159)	(42)
Held to Maturity, Fair Value, total	$ 1,455	$ 1,563

Held to maturity debt securities unrecognized holding gains.

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- Definition

Held to maturity debt securities unrecognized holding losses.

+ Details

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- Definition

This item represents the total of all debt securities grouped by maturity dates, at cost, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments, as defined), and fair value hedge accounting adjustments, if any, which are classified as held-to-maturity.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-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 FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27232-111563

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- Definition

This item represents the aggregate fair value of investments in debt securities as of the balance sheet date and which are categorized as held-to-maturity.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 19

-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 FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 137

-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

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27232-111563

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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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