Income tax provision (Details)	6 Months Ended	12 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
Reconciliation of effective income tax rate
Income tax at federal statutory rate	21.00%	21.00%
Change in valuation allowances	14.90%	0.10%
Tax impact of share-based compensation	5.30%	0.90%
State income tax, net of federal income tax benefit	2.60%	2.40%
Non-deductible executive compensation	2.40%	1.70%
Foreign tax rate differences	1.70%	1.70%
Tax on repatriation of foreign earnings	1.40%	4.90%
Non-deductible acquisition costs	0.10%	1.50%
Sale of business (Note 6)	(18.30%)	0.00%
Research and development tax credit	(1.10%)	(0.90%)
Other	(0.30%)	(0.20%)
Effective tax rate	29.70%	33.10%