Pensions and Other Post Employment Benefit Plans - Summary of Principal Assumptions used in Determining Pension Benefit Obligations for Group's Plan (Details)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Disclosure Of Defined Benefit Plans [Line Items]
Discount rate	2.30%	0.35%	0.15%
Future salary increases	1.20%	1.00%	1.00%
Future pensions increases	0.00%	0.00%
Demographic assumptions	BVG 2020 GT	BVG 2020 GT
Men
Disclosure Of Defined Benefit Plans [Line Items]
Retirement age	65 years	65 years
Women
Disclosure Of Defined Benefit Plans [Line Items]
Retirement age	64 years	64 years

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
-Name IAS
-Number 19
-IssueDate 2022-03-24
-Paragraph 144
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_144&doctype=Standard
-URIDate 2022-03-24

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The expected rate of increases in pension 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]]

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The expected rate of salary increases 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]]

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

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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.

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Actuarial assumption of demographic assumptions.

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