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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, 2022 USD ($) | Dec. 31, 2021 USD ($)
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 |
Rate for Debt Investment | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Volatility |  | 36.0
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”) | 4.0 | 9.0
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”) | 12.0 | 18.0
Rate for Debt Investment | Maximum | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Volatility | 31.0 |
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 |
Rate for Equity Investment | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Volatility |  | 36.0
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”) | 6.0 | 11.0
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”) | 12.0 | 18.0
Rate for Equity Investment | Maximum | Volatility |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Volatility | 31.0 |
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% | $ 372 |
Changes of Fair Value, If the Rate of Input changes by +1% | 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% | 93 | $ 93
Changes of Fair Value, If the Rate of Input changes by +1% | (93) | 92
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% | 23 | (9)
Changes of Fair Value, If the Rate of Input changes by +1% | 24 | 2
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% | 175 |
Changes of Fair Value, If the Rate of Input changes by +1% | 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% | 26 | 26
Changes of Fair Value, If the Rate of Input changes by +1% | (25) | (26)
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% | 16 | 13
Changes of Fair Value, If the Rate of Input changes by +1% | $ (10) | $ (12)

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