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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, 2024 USD ($) | Dec. 31, 2023 USD ($)
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”) | 13 | 12
Rate for Debt Investment | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Volatility | 29 | 29
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 | 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”) | 13 | 12
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”) | 48 | 30
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% | $ 324 | $ 90
Changes of Fair Value, If the Rate of Input changes by +1% | (352) | (121)
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% | 62 | 63
Changes of Fair Value, If the Rate of Input changes by +1% | (62) | (63)
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% | 99 | 22
Changes of Fair Value, If the Rate of Input changes by +1% | (36) | (86)
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% | 28 | 67
Changes of Fair Value, If the Rate of Input changes by +1% | (20) | (58)
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% | 1 | 4
Changes of Fair Value, If the Rate of Input changes by +1% | (1) | (3)
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% | (1) | 3
Changes of Fair Value, If the Rate of Input changes by +1% | $ 2 | $ (2)

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