Note to Schedule One - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Condensed Financial Information Of Parent Company Only Disclosure [Abstract]
Reserves and registered capital of PRC subsidiaries	$ 408,536,000	$ 408,600,000	$ 408,200,000	$ 407,600,000	$ 362,800,000
Minimum percentage of restricted net assets of consolidated and unconsolidated subsidiaries to consolidated net assets to file condensed financial information					25.00%
Cash dividend was declared by subsidiaries	0	0	0	0	$ 0	$ 0
Cash dividend was paid by subsidiaries	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0

The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

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