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Derivative Financial Instruments - Summary of Company's Net Credit Exposure Relating to Oil and Gas Swaps and Options with Bank Counterparties (Detail) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Oil and Natural Gas Swaps and Options [Member] |  |
Credit Derivatives [Line Items] |  |
Credit exposure | $ 15,778 | $ 8,074

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