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Fair Value Measurements (Schedule Of Changes In Fair Value Of Level 3 Financial Assets And Liabilities Held At Fair Value) (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010
Municipal Securities [Member] |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Beginning Balance | $ 1,624 | $ 3,322
Realized gains (losses) included in earnings | 39 | (108)
Purchase | 0 | 0
Sales | (1,663) | (1,590)
Issuances | 0 | 0
Settlements | 0 | 0
Ending Balance | 0 | 1,624
The amount of total (losses) gains for the period included in earnings attributable to assets still held at December 31 | 0 | (83)
Collateralized Debt Obligations [Member] |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Beginning Balance | 55,692 | 47,473
Realized gains (losses) included in earnings | (9,300) | 13,388
Purchase | 0 | 0
Sales | 0 | 0
Issuances | 0 | 0
Settlements | 1,111 | (5,169)
Ending Balance | 47,503 | 55,692
The amount of total (losses) gains for the period included in earnings attributable to assets still held at December 31 | (8,189) | 12,810
Partnership Interest In A Private Credit Fund [Member] |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Beginning Balance | 0 |
Realized gains (losses) included in earnings | 8 |
Purchase | 10,000 |
Sales | 0 |
Issuances | 0 |
Settlements | 0 |
Ending Balance | 10,008 |
The amount of total (losses) gains for the period included in earnings attributable to assets still held at December 31 | $ 8 |

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- Definition Amount Of Total Losses Gains For Period Included In Earnings Attributable To Assets Still Held + References No definition available. + Details
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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of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph c(1) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 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 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 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 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 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 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 + Details
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