Derivative Financial Instruments (Counterparty Credit Quality With Respect To Fair Value Of OTC Derivatives Assets) (Details) $ in Thousands	Mar. 31, 2017 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
A- or higher	$ 225,496
BBB- to BBB	62,994
BB or lower	28,130
Unrated	38,363
Total OTC derivative assets included in Trading assets	$ 354,983

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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No definition available.

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