Derivative Financial Instruments (Counterparty Credit Quality With Respect To Fair Value Of OTC Derivatives Assets) (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair value of OTC derivatives assets, Counterparty credit quality, A- or higher	$ 195,503
Fair value of OTC derivatives assets, Counterparty credit quality, BBB- to BBB+	76,796
Fair value of OTC derivatives assets, Counterparty credit quality, BB+ or lower	50,581
Fair value of OTC derivatives assets, Counterparty credit quality, Unrated	59,934
Total	$ 382,814

Fair value of OTC derivatives assets, counterparty credit quality A- or higher.

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Fair value of OTC derivatives assets, counterparty credit quality BB or lower.

No definition available.

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Fair value of OTC derivatives assets, counterparty credit quality BBB- to BBB+.

No definition available.

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Fair value of OTC derivatives assets, counterparty credit quality unrated.

No definition available.

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OTC Derivative Assets Included In Financial Instruments Owned.

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