Retirement benefit plan - Changes in Fair Value of Plan Assets (Details) - CHF (SFr) SFr in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
|
| Changes in fair value of plan assets [Abstract] | |||
| At beginning of period | SFr (8,844) | SFr (5,770) | SFr (3,213) |
| Employer's contributions | 1,853 | 1,804 | 1,567 |
| At end of period | (8,645) | (8,844) | (5,770) |
| Expected contributions by the employer to be paid to the post-employment benefit plans during the annual period beginning after the end of the reporting period | 1,500 | ||
| Fair Value of Plan Assets | |||
| Changes in fair value of plan assets [Abstract] | |||
| At beginning of period | 43,611 | 35,290 | 29,197 |
| Interest income | 438 | 574 | 705 |
| Employees' contributions | 1,665 | 1,583 | 1,396 |
| Employer's contributions | 1,853 | 1,804 | 1,567 |
| Benefits (deposited)/paid | (4,119) | 2,504 | 1,265 |
| Gains and (losses) on settlement / curtailment | (4,300) | ||
| Return on plan assets excluding interest income | 467 | 1,856 | 1,160 |
| At end of period | SFr 39,615 | SFr 43,611 | SFr 35,290 |
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Increase (decrease) in net defined benefit liability (asset) resulting from benefits deposited No definition available.
|
| X | ||||||||||
- 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 [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- 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 [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition The estimate of the expected contributions to be made to a defined benefit plan for the next annual reporting period. [Refer: Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from settlements. Settlements are transactions that eliminate all further legal or constructive obligations for part or all of the benefits provided under a defined benefit plan, other than a payment of benefits to, or on behalf of, employees that is set out in the terms of the plan and included in the actuarial assumptions. [Refer: Net defined benefit liability (asset); Defined benefit plans [domain]; Actuarial assumptions [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- References Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- 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 [domain]; Increase (decrease) in net defined benefit liability (asset) resulting from interest expense (income)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Details
|