Derivative Financial Instruments (Counterparty Credit Quality With Respect To Fair Value Of OTC Derivatives Assets) (Details) $ in Thousands	Sep. 30, 2018 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
A- or higher	$ 137,910
BBB- to BBB	20,490
BB or lower	74,097
Unrated	18,813
Total OTC derivative assets included in Trading assets	$ 251,310

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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