Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in securities - current		$ 7,950
Investment in securities - noncurrent	$ 5,777	2,371
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in securities - current		7,950
Investment in securities - noncurrent	5,777	2,371
Total	6,090	10,634
Fair Value, Measurements, Recurring \| Fair Value Measurements Using Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	313	313
Fair Value, Measurements, Recurring \| Fair Value Measurements Using Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in securities - current		7,950
Investment in securities - noncurrent	5,777	2,371
Total	5,777	10,321
Fair Value, Measurements, Recurring \| Bank Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash - time deposits	313	313
Fair Value, Measurements, Recurring \| Bank Time Deposits \| Fair Value Measurements Using Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash - time deposits	$ 313	$ 313

Restricted cash and cash equivalents, fair value disclosure.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

+ References

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