Post-Employment Benefits - Summary of Sensitivity of Defined Benefit Obligation (Parenthetical) (Detail) - Actuarial liabilities [member]	Dec. 31, 2021
BD and CV Plans [member] \| Actuarial assumption of interest rates [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Percentage increase in assumptions	0.50%
Percentage decrease in assumptions	0.50%
BD and CV Plans [member] \| Actuarial assumption of mortality rates [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Percentage increase in assumptions	5.00%
Percentage decrease in assumptions	5.00%
BD and CV Plans [member] \| Medical care cost [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Percentage increase in assumptions	1.00%
Percentage decrease in assumptions	1.00%
Other post employment benefits [member] \| Actuarial assumption of interest rates [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Percentage increase in assumptions	0.50%
Percentage decrease in assumptions	0.50%
Other post employment benefits [member] \| Actuarial assumption of mortality rates [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Percentage increase in assumptions	5.00%
Percentage decrease in assumptions	5.00%
Other post employment benefits [member] \| Medical care cost [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Percentage increase in assumptions	1.00%
Percentage decrease in assumptions	1.00%

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 reasonably possible percentage of the decrease in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
-Paragraph 145
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- Definition

The reasonably possible percentage of the increase in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]]

+ References

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