Post-employment Benefits - Summary of Main Assumptions Used in Actuarial Valuation of Retirement Plans (Detail)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Jan. 01, 2021	Jan. 01, 2020
Disclosure of defined benefit plans [line items]
Mortality table	AT-2000	AT-2000
Discount rate	9.46%	7.64%	7.64%	7.64%
Inflation	4.00%	4.00%
Actuarial method	Projected Unit Credit	Projected Unit Credit

The discount rate used as the significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The expected rate of inflation that is used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [member]; Defined benefit obligation, at present value; Actuarial assumptions [member]]

+ References

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- Definition

The description of the methods and assumptions used when preparing a sensitivity analysis for significant actuarial assumptions. [Refer: Actuarial assumptions [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
-Paragraph 145
-Subparagraph b
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-URIDate 2021-03-24

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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.

+ References

No definition available.

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- Definition

Description of Mortality

+ References

No definition available.

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