Derivative Financial Instruments - Counterparty Credit Quality with Respect to Fair Value of OTC Derivatives Assets (Details) $ in Thousands	Feb. 29, 2020 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
A- or higher	$ 221,812
BBB- to BBB	49,721
BB or lower	295,398
Unrated	196,473
Total OTC derivative assets included in Financial instruments owned	$ 763,404

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

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

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

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Fair Value Of Over Counter Derivatives Assets Counterparty Credit QualityA Or Higher

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OTC Derivative Assets Included In Financial Instruments Owned.

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