Long-lived Assets (Property And Equipment, net) by Geographic Area (Detail) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$ 218,966	$ 188,398	$ 167,417
Taiwan
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	208,415	177,335	155,334
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	10,006	10,369	11,118
Others
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$ 545	$ 694	$ 965

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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