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Financial instruments owned - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2023 | Mar. 31, 2022
Financial Instruments Owned at Fair Value [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Debt and Equity Securities, Gain (Loss) | $ 4,722 | $ 4,316

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- Definition Amount of unrealized and realized gain (loss) on investment in debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(9)(a)) -URI https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(7)(c)) -URI https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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