Employee Stock Option Plan (Details 11) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total employee stock option plans expenses	$ 2,941	$ 3,253	$ 1,578
Cost of revenue [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total employee stock option plans expenses	255	639	360
Research and development expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total employee stock option plans expenses	233	72	118
Selling, general and administrative expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total employee stock option plans expenses	$ 2,453	$ 2,542	$ 1,100