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Summary of Significant Unobservable Inputs Used in Fair Value Measurements Categorized Within Level 3 of Fair Value Hierarchy (Detail) - Level 3 - Option Pricing Method $ in Thousands | 12 Months Ended
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Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Rate for Debt Investment | Discount Rate for Future Cash Flows |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Discount rate for future cash flows | 38.5 | 38.5
Rate for Debt Investment | Discount for Lack of Marketability (“DLOM”) |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Discount for lack of marketability (“DLOM”) | 12 |
Rate for Debt Investment | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Volatility | 29 |
Rate for Debt Investment | Minimum | Discount for Lack of Marketability (“DLOM”) |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Discount for lack of marketability (“DLOM”) |  | 4
Rate for Debt Investment | Minimum | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Volatility |  | 28
Rate for Debt Investment | Maximum | Discount for Lack of Marketability (“DLOM”) |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Discount for lack of marketability (“DLOM”) |  | 12
Rate for Debt Investment | Maximum | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Volatility |  | 31
Rate for Equity Investment | Discount Rate for Future Cash Flows |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Discount rate for future cash flows | 38.5 | 38.5
Rate for Equity Investment | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Volatility | 29 |
Rate for Equity Investment | Minimum | Discount for Lack of Marketability (“DLOM”) |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Discount for lack of marketability (“DLOM”) | 12 | 6
Rate for Equity Investment | Minimum | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Volatility |  | 28
Rate for Equity Investment | Maximum | Discount for Lack of Marketability (“DLOM”) |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Discount for lack of marketability (“DLOM”) | 30 | 12
Rate for Equity Investment | Maximum | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Volatility |  | 31
Debt Securities | Discount Rate for Future Cash Flows |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Changes of Fair Value, If the Rate of Input changes by -1% | $ 90 | $ 372
Changes of Fair Value, If the Rate of Input changes by +1% | 121 | 262
Debt Securities | Discount for Lack of Marketability (“DLOM”) |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Changes of Fair Value, If the Rate of Input changes by -1% | 63 | 93
Changes of Fair Value, If the Rate of Input changes by +1% | (63) | (93)
Debt Securities | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Changes of Fair Value, If the Rate of Input changes by -1% | 22 | 23
Changes of Fair Value, If the Rate of Input changes by +1% | 86 | 24
Equity Securities | Discount Rate for Future Cash Flows |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Changes of Fair Value, If the Rate of Input changes by -1% | 67 | 175
Changes of Fair Value, If the Rate of Input changes by +1% | (58) | (170)
Equity Securities | Discount for Lack of Marketability (“DLOM”) |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Changes of Fair Value, If the Rate of Input changes by -1% | 4 | 26
Changes of Fair Value, If the Rate of Input changes by +1% | (3) | (25)
Equity Securities | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Changes of Fair Value, If the Rate of Input changes by -1% | 3 | 16
Changes of Fair Value, If the Rate of Input changes by +1% | $ (2) | $ (10)

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