Interim condensed consolidated statement  of cash flows 
| For the six months ended 30 June | 
 | 
 | 
 | 
| in CHF 1,000 | Note | 2020 | 2019 | 
| 
 | 
 | 
 | 
 | 
| Profit for the period | 
 | 66,708 | 67,264 | 
| 
 | 
 | 
 | 
 | 
| Adjustments for: | 
 | 
 | 
 | 
| Depreciation and amortization | 
 | 29,679 | 24,056 | 
| Total finance result, net | 
 | –11,161 | –10,857 | 
| Share of result of joint ventures and associated companies | 
 | –417 | – | 
| Tax expense | 
 | 17,510 | 14,505 | 
| Other non-cash items | 
 | 15,352 | 11,320 | 
| Change in trade receivables | 
 | –133,472 | –173,284 | 
| Change in other receivables, prepayments and contract assets | 
 | –66,413 | –282,307 | 
| Change in trade and other payables | 
 | 250,556 | 141,821 | 
| Change in accrued expenses and contract liabilities | 
 | 56,977 | 207,325 | 
| Income taxes paid | 
 | –18,586 | –14,898 | 
| 
 | 
 | 
 | 
 | 
| Net cash generated from/(used in) operating activities | 
 | 206,734 | –15,055 | 
| Purchases of tangible and intangible assets | 
 | –10,760 | –11,448 | 
| Proceeds from sale of tangible and intangible assets | 
 | 173 | 128 | 
| Purchases of financial assets | 
 | –2,959 | –7,196 | 
| Loans granted | 
 | –957 | –338 | 
| Loan repayments received | 
 | 3,246 | 1,355 | 
| Interest received | 
 | 674 | 1,037 | 
| Acquisition of businesses (net of cash) | 3 | –35,004 | 56,667 | 
| 
 | 
 | 
 | 
 | 
| Net cash from/(used) in investing activities | 
 | –45,587 | 40,205 | 
| Proceeds from financial liabilities | 
 | 376,816 | 684,875 | 
| Repayments of financial liabilities | 
 | –262,752 | –704,198 | 
| Payment of contingent consideration liabilities | 4 | –1,556 | –3,149 | 
| Purchase of treasury shares | 
 | – | –2,462 | 
| Interest paid | 
 | –4,076 | –3,099 | 
| Dividends paid to owners of the parent | 7 | –32,460 | –24,855 | 
| 
 | 
 | 
 | 
 | 
| Net cash from/(used in) financing activities | 
 | 75,972 | –52,888 | 
| 
 | 
 | 
 | 
 | 
| Net (decrease)/increase in cash and cash equivalents | 
 | 237,118 | –27,738 | 
| Cash and cash equivalents at beginning of period | 
 | 313,490 | 154,142 | 
| Net foreign exchange difference on cash and cash equivalents | 
 | –10,210 | 516 | 
| 
 | 
 | 
 | 
 | 
| Cash and cash equivalents at end of period | 
 | 540,398 | 126,920 |