Stockholders' Equity - Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2023	May 31, 2022	May 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock based compensation pre tax amount	$ 11,158	$ 10,692	$ 8,625
Cost of sales
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock based compensation pre tax amount	793	827	768
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock based compensation pre tax amount	1,459	1,298	1,152
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock based compensation pre tax amount	2,922	2,568	1,641
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock based compensation pre tax amount	$ 5,984	$ 5,999	$ 5,064