Operating Segments (Schedule Of Sales And Long-Lived Assets By Country) (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Segment Reporting Information [Line Items]
Sales and other operating revenues	$ 2,569,824	$ 2,103,601	$ 1,983,357
Long-Lived Assets	645,185	651,687	594,865
United States [Member]
Segment Reporting Information [Line Items]
Sales and other operating revenues	530,467	495,322	369,074
Long-Lived Assets	343,470	344,276	266,258
Belgium [Member]
Segment Reporting Information [Line Items]
Sales and other operating revenues	395,616	283,072	366,476
China [Member]
Segment Reporting Information [Line Items]
Sales and other operating revenues	204,139	97,826	52,837
Philippines
Segment Reporting Information [Line Items]
Sales and other operating revenues	149,867	147,876	94,493
Poland
Segment Reporting Information [Line Items]
Sales and other operating revenues	119,629	90,270	97,001
Germany [Member]
Segment Reporting Information [Line Items]
Sales and other operating revenues	108,844	93,057	94,519
FRANCE
Segment Reporting Information [Line Items]
Sales and other operating revenues	64,563	39,307	26,480
MEXICO
Segment Reporting Information [Line Items]
Sales and other operating revenues	51,847	29,514	51,448
NETHERLANDS
Segment Reporting Information [Line Items]
Sales and other operating revenues	51,843	45,297	40,754
Brazil [Member]
Segment Reporting Information [Line Items]
Long-Lived Assets	134,232	136,653	134,909
Mozambique [Member]
Segment Reporting Information [Line Items]
Long-Lived Assets	38,979	40,228	44,206
All Other Countries [Member]
Segment Reporting Information [Line Items]
Sales and other operating revenues	893,009	782,060	790,275
Long-Lived Assets	$ 128,504	$ 130,530	$ 149,492