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Fair Value Measurement (Summary Of Changes In Fair Value Of Level 3 Financial Assets And Financial Liabilities Held At Fair Value) (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended
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Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012
Collateralized Debt Obligations [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Beginning Balance | $ 39,723 | $ 52,983 | $ 42,801 | $ 47,503
Realized (losses) gains included in earnings | (731) | (1,658) | 377 | 3,822
Purchases | 0 | 25,000 | 0 | 25,000
Sales |  |  | (4,186) |
Ending Balance | 38,992 | 76,325 | 38,992 | 76,325
The amount of total (losses) gains for the period included in earnings attributable to assets still held at June 30 | (731) | (1,658) | 894 | 3,822
Partnership Interest In Private Credit Fund [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Beginning Balance | 11,592 | 10,510 | 11,306 | 10,008
Realized (losses) gains included in earnings | 398 | 520 | 684 | 1,022
Purchases |  | 0 | 0 | 0
Ending Balance | 11,990 | 11,030 | 11,990 | 11,030
The amount of total (losses) gains for the period included in earnings attributable to assets still held at June 30 | $ 398 | $ 520 | $ 684 | $ 1,022

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- Definition Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + 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)(1) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + 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=25499696&loc=d3e19207-110258 + Details
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- Definition Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + 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=25499696&loc=d3e19207-110258 + Details
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