Derivative Financial Instruments - Counterparty Credit Quality with Respect to Fair Value of OTC Derivatives Assets (Details) $ in Thousands	Feb. 28, 2021 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
A- or higher	$ 162,505
BBB- to BBB+	38,774
BB+ or lower	201,073
Unrated	262,379
Total OTC derivative assets included in Financial instruments owned	$ 664,731

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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