Supplemental Balance Sheets and Statements of Operations - Other Expenses and Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Accrued expenses:
Salaries, wages, and related employee costs	$ 39,605	$ 61,880
Interest	47	211
Restructuring	1,744	1,869
Vacation	9,668	10,364
Lease obligations	8,960	947
Antitrust settlements and regulatory costs	75,086	9,517
Contract liabilities	6,035	256
Stock Returns	3,690	2,539
Property, sales, and other taxes	2,342	1,854
Other	6,453	4,324
Total accrued expenses	167,622	93,761
Other non-current obligations:
Pension plans	79,512	82,717
Lease obligations	24,108	986
Employee separation liability	7,044	7,640
Deferred compensation	353	2,285
Contract liabilities	60,638	13,412
Customer deposits	3,742	3,689
Derivatives	6,295	0
Antitrust settlements and regulatory costs	0	13,168
Uncertain tax positions	6,306	2,415
Deferred rent	0	5,366
Government subsidies	1,677	1,247
Restructuring	89	312
Other	3,628	3,393
Total other non-current obligations	193,392	136,630
Other (income) expense, net:
Net foreign exchange (gains) losses	(6,762)	(7,230)	$ 13,145
Post retirement and pension plan non-service costs	439	366	210
Curtailment on pension plans	1,949	0	0
Loss on early extinguishment of debt	0	15,946	486
R&D grant reimbursements and grant income	(1,595)	(4,559)	(787)
Other	(1,613)	10	(1,638)
Total other (income) expense, net	$ (4,356)	$ 4,513	$ 14,692