Post-employment Benefits - Summary of Amount Recognised as Accumulated Other Comprehensive Income (Detail) - BRL (R$) R$ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disclosure of net defined benefit liability (asset) [abstract]
Accumulated at the beginning of the year	R$ 59,904	R$ 66,305	R$ 170,702
Actuarial (gain) loss arising from financial assumptions	183,156	58,250	(211,030)
Actuarial loss (gain) arising from experience adjustment	(77,112)	(30,267)	1,216
Actuarial loss arising from demographic assumptions		(14)
Return on investments in the year (excluding interest income)	(24,145)	(34,370)	105,417
Accumulated at the end of the year	R$ 141,803	R$ 59,904	R$ 66,305

Accumulated liability asset of defined benefit plans.

No definition available.

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- Definition

The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in demographic assumptions that result in remeasurements of the net defined benefit liability (asset). Demographic assumptions deal with matters such as: (a) mortality; (b) rates of employee turnover, disability and early retirement; (c) the proportion of plan members with dependants who will be eligible for benefits; (d) the proportion of plan members who will select each form of payment option available under the plan terms; and (e) claim rates under medical plans. [Refer: Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
-Paragraph 141
-Subparagraph c
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_141_c_ii&doctype=Standard
-URIDate 2021-03-24

+ Details

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- Definition

The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in financial assumptions that result in remeasurements of the net defined benefit liability (asset). Financial assumptions deal with items such as: (a) the discount rate; (b) benefit levels, excluding any cost of the benefits to be met by employees, and future salary; (c) in the case of medical benefits, future medical costs, including claim handling costs (ie the costs that will be incurred in processing and resolving claims, including legal and adjuster's fees); and (d) taxes payable by the plan on contributions relating to service before the reporting date or on benefits resulting from that service. [Refer: Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
-Paragraph 141
-Subparagraph c
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_141_c_iii&doctype=Standard
-URIDate 2021-03-24

+ Details

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- Definition

The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from experience adjustments that result in remeasurements of the net defined benefit liability (asset). Experience adjustments deal with the effects of differences between the previous actuarial assumptions and what has actually occurred. [Refer: Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
-Paragraph 141
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_141_c&doctype=Standard
-URIDate 2021-03-24

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- References

No definition available.

+ Details

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- Definition

The decrease (increase) in the net defined benefit liability (asset) resulting from the return on plan assets, excluding amounts included in interest income or expense. The return on plan assets is interest, dividends and other revenue derived from the plan assets, together with realised and unrealised gains or losses on the plan assets, less any costs of managing plan assets and less any tax payable by the plan itself, other than tax included in the actuarial assumptions used to measure the present value of the defined benefit obligation. [Refer: Plan assets [member]; Net defined benefit liability (asset); Actuarial assumptions [member]; Increase (decrease) in net defined benefit liability (asset) resulting from interest expense (income)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
-Paragraph 141
-Subparagraph c
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_141_c_i&doctype=Standard
-URIDate 2021-03-24

+ Details

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