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Arbitrage Trading Account | 12 Months Ended
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Dec. 31, 2023
Trading Securities and Derivative Instruments [Abstract] |
Arbitrage Trading Account | Arbitrage Trading Account At December 31, 2023 and 2022, the fair value and carrying value of the arbitrage trading account were $938 million and $944 million, respectively. The primary focus of the trading account is merger arbitrage. Merger arbitrage is the business of investing in the securities of publicly held companies which are the targets in announced tender offers and mergers. Arbitrage investing differs from other types of investing in its focus on transactions and events believed likely to bring about a change in value over a relatively short time period (usually four months or less). The Company uses put options and call options in order to mitigate the impact of potential changes in market conditions on the merger arbitrage trading account. These options are reported at fair value. As of December 31, 2023, the fair value of long option contracts outstanding was $185 thousand (notional amount of $75 million) and the fair value of short option contracts outstanding was $9 million (notional amount of $75 million). Other than with respect to the use of these trading account securities, the Company does not make use of derivatives.

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