Financial risk management - Summary of Sensitivity Analysis of Fair Value Measurement to Changes in Unobservable Inputs, Liabilities (Parenthetical) (Detail) - Interest rate, measurement input [member] - Interest rate risk [member]  | 
Dec. 31, 2021  | 
Dec. 31, 2020  | 
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| Disclosure of sensitivity analysis of fair value measurement to changes in unobservable inputs, liabilities [line items] | ||
| Percentage of reasonably possible increase in unobservable input, liabilities | 0.10% | 0.10% | 
| Percentage of reasonably possible decrease in unobservable input, liabilities | 0.10% | 0.10% | 
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. No definition available. 
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- Definition The percentage of a reasonably possible decrease in an unobservable input used in fair value measurement of liabilities. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- Definition The percentage of a reasonably possible increase in an unobservable input used in fair value measurement of liabilities. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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