Other Contingent Liabilities And Other Matters (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Sep. 30, 2022	Sep. 30, 2022	Sep. 30, 2021	Mar. 31, 2022
Other Contingent Liabilities and Other Matters [Line Items]
Other contingent liabilities	$ 1,000	$ 1,000
Net provision for losses (recoveries) on advances to suppliers		(1,034)	$ (44)
Unsecured variable rate debt	150,000	150,000
Proceeds from Sales of Business, Affiliate and Productive Assets	1,300
Sales agreement to sell common stock of subsidiary company, value	8,500
November 2020 Stock Repurchase Plan [Member]
Other Contingent Liabilities and Other Matters [Line Items]
Stock repurchase program authorized amount	100,000	100,000
Stock repurchase program remaining authorized repurchase amount	93,000	93,000
November 2022 Stock Repurchase Plan [Member]
Other Contingent Liabilities and Other Matters [Line Items]
Stock repurchase program authorized amount	100,000	100,000
Five-year term loan [Member]
Other Contingent Liabilities and Other Matters [Line Items]
Long-Term Debt	225,000	225,000
Seven-year term loan [Member]
Other Contingent Liabilities and Other Matters [Line Items]
Long-Term Debt	295,000	295,000
Advances to suppliers [Member]
Other Contingent Liabilities and Other Matters [Line Items]
Advances to suppliers current and non-current	122,000	122,000	98,000	$ 153,000
Valuation allowances	14,000	14,000	14,000	19,000
Net provision for losses (recoveries) on advances to suppliers		(1,000)	(44)
Recoverable value added tax credits [Member]
Other Contingent Liabilities and Other Matters [Line Items]
Aggregate balance of recoverable value added tax credits	70,000	70,000	55,000	67,000
Valuation allowances	24,000	24,000	$ 20,000	$ 21,000
Santa Catarina [Member]
Other Contingent Liabilities and Other Matters [Line Items]
Brazil audit assessment for tax, penalties, and interest on recoverable value added tax credits	9,000	9,000
Reduced Brazil audit assessment for tax, penalties, and interest on recoverable value added tax credits		9,000
Loss contingency amount accrued	0	0
Santa Catarina [Member] | Minimum [Member]
Other Contingent Liabilities and Other Matters [Line Items]
Estimate of possible loss on remaining VAT audit assessment	0	0
Santa Catarina [Member] | Maximum [Member]
Other Contingent Liabilities and Other Matters [Line Items]
Estimate of possible loss on remaining VAT audit assessment	9,000	9,000
Parana [Member]
Other Contingent Liabilities and Other Matters [Line Items]
Brazil audit assessment for tax, penalties, and interest on recoverable value added tax credits	10,000	10,000
Reduced Brazil audit assessment for tax, penalties, and interest on recoverable value added tax credits		3,000
Loss contingency amount accrued	0	0
Parana [Member] | Minimum [Member]
Other Contingent Liabilities and Other Matters [Line Items]
Estimate of possible loss on remaining VAT audit assessment	0	0
Parana [Member] | Maximum [Member]
Other Contingent Liabilities and Other Matters [Line Items]
Estimate of possible loss on remaining VAT audit assessment	$ 3,000	$ 3,000