Fair Value Measurement (Schedule Of Changes In Fair Value Of Level 3 Financial Assets And Liabilities Held At Fair Value) (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Municipal Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Beginning Balance	$ 0	$ 1,357	$ 1,624	$ 3,322
Realized (losses) gains included in earnings	0	(3)	39	(378)
Purchase	0	0	0	0
Sales	0	0	(1,663)	(1,590)
Issuances	0	0	0	0
Settlements	0	0	0	0
Ending Balance	0	1,354	0	1,354
The amount of total (losses) gains for the period included in earnings attributable to assets still held at September 30	0	(3)	0	(353)
Collateralized Debt Obligations [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Beginning Balance	55,724	47,585	55,692	47,473
Realized (losses) gains included in earnings	(11,857)	4,859	(12,936)	9,562
Purchase	0	0	0	0
Sales	0	0	0	0
Issuances	0	0	0	0
Settlements	0	(578)	1,111	(5,169)
Ending Balance	43,867	51,866	43,867	51,866
The amount of total (losses) gains for the period included in earnings attributable to assets still held at September 30	$ (11,857)	$ 4,281	$ (11,825)	$ 8,983

Amount Of Total Losses Gains For Period Included In Earnings Attributable To Assets Still Held

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- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

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- Definition

Issues that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

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- Definition

Purchases that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

+ Details

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- Definition

Sales that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

+ Details

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- Definition

Settlements that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

+ Details

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Balance Type:	credit
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- Definition

This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c

-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 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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- Definition

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.

+ Details

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