Retirement Benefit and Other Post-retirement Obligations - Summary of Effect of a Half Percentage Point Increase and Decrease in the Inflation Rate (Parenthetical) (Detail) - Inflation [member]	Dec. 31, 2022
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Movement in inflation sensitivity analysis	1.00%
Movement in inflation sensitivity analysis	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.

+ Details

Name:	ifrs-full_DisclosureOfSensitivityAnalysisForActuarialAssumptionsLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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 2022-03-24
-Paragraph 145
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_145_a&doctype=Standard
-URIDate 2022-03-24

+ Details

Name:	ifrs-full_PercentageOfReasonablyPossibleDecreaseInActuarialAssumption
Namespace Prefix:	ifrs-full_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- 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

+ Details

Name:	ifrs-full_PercentageOfReasonablyPossibleIncreaseInActuarialAssumption
Namespace Prefix:	ifrs-full_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	ifrs-full_ActuarialAssumptionsAxis=ifrs-full_ActuarialAssumptionOfExpectedRatesOfInflationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: