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Equity Securities Without Readily Determinable Fair Values (Equity securities without readily determinable fair values) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Equity Method And Other Investments [Abstract]
Total	$ 17,383	$ 17,383

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Equity Method And Other Investments

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Equity Method And Other Investments [Abstract]

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