Pensions and Other Post Employment Benefit Plans - Changes in the Fair Value of Plan Assets (Details) - CHF (SFr) SFr in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Disclosure Of Defined Benefit Plans [Line Items]
Fair value of plan assets at 1 January	SFr 4,821
Fair value of plan assets at December 31,	6,403	SFr 4,821
Plan Assets
Disclosure Of Defined Benefit Plans [Line Items]
Fair value of plan assets at 1 January	4,821	4,159
Expected return	26	6
Contributions by employer	429	289
Contributions by employees	185	126
Benefits paid from plan assets	(770)	(1,479)
Contributions paid by participants	1,686	1,702
Actuarial gains / (losses)	26	18
Fair value of plan assets at December 31,	SFr 6,403	SFr 4,821

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)]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2022-03-24
-Paragraph 141
-Subparagraph c
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-URIDate 2022-03-24

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- Definition

The decrease (increase) in net defined benefit liability (asset) resulting from contributions to a defined benefit plan by the employer. [Refer: Net defined benefit liability (asset); Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2022-03-24
-Paragraph 141
-Subparagraph f
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_141_f&doctype=Standard
-URIDate 2022-03-24

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- Definition

The decrease (increase) in the net defined benefit liability (asset) resulting from contributions to a defined benefit plan by plan participants. [Refer: Net defined benefit liability (asset); Defined benefit plans [member]]

+ References

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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

The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2022-03-24
-Paragraph 57
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_57_a&doctype=Standard
-URIDate 2022-03-24

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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
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-Number 19
-IssueDate 2022-03-24
-Paragraph 141
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-URIDate 2022-03-24

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- Definition

Benefits paid from plan assets.

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No definition available.

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- Definition

Contributions to plan by employees net defined benefit liability asset.

+ References

No definition available.

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