Schedule of Long-term Loans (Parenthetical) (Detail)	12 Months Ended
Dec. 31, 2020
Loan from Bank of Beijing
Debt Instrument [Line Items]
Debt instrument, interest rate	6.46%
Debt instrument, maturity date	Aug. 14, 2022
Loan from Bank of China
Debt Instrument [Line Items]
Debt instrument, interest rate	6.072%
Debt instrument, maturity date	Nov. 07, 2028
Loan from Xiamen International Bank
Debt Instrument [Line Items]
Debt instrument, interest rate	7.40%
Debt instrument, maturity date	Jan. 06, 2022
Loan from Industrial Bank
Debt Instrument [Line Items]
Debt instrument, interest rate	6.175%
Debt instrument, maturity date	Oct. 20, 2022

Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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