Profit Interest Units of SIS Holdings LP - Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation costs	$ 3,460	$ 4,235
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation costs	504	503
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation costs	1,844	2,211
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation costs	359	360
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation costs	$ 753	$ 1,161