Arbitrage Trading Account (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Derivative [Line Items]
Arbitrage trading account	$ 724,000	$ 944,000
Long \| Options held
Derivative [Line Items]
Fair value of derivative	0
Notional amount of derivative	$ (1)

Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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