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Business Segment Information - Additional Information (Detail)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Minimum | Geographic Concentration Risk | Revenue, Operating Income, Identifiable Assets or Equity | Peoples Republic Of China Including Hong Kong      
Concentration Risk [Line Items]      
Concentration percentage 10.00% 10.00% 10.00%