Guarantees, Other Contingent Liabilities, And Other Matters (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Mar. 31, 2015
Guarantees, Other Contingent Liabilities, and Other Matters [Line Items]
Company total exposure under guarantees	$ 2,000
Face amount of guarantee including unpaid accrued interest	4,000	$ 8,000	$ 17,000
Fair value of the guarantees	1,569	2,390	1,674
Other contingent liabilities	3,000
Advances to suppliers current and non-current	96,000	128,000	156,000
Valuation allowance amount related to advances to suppliers	34,000	44,000	35,000
Provision for loss on uncollectible advances to suppliers	2,000	1,000
Aggregate balance of recoverable value added tax credits	61,000	70,000	60,000
Valuation allowance on recoverable value added tax credits	23,000	$ 36,000	$ 23,000
Santa Catarina [Member]
Guarantees, Other Contingent Liabilities, and Other Matters [Line Items]
Brazil audit assessment for tax, penalties, and interest on recoverable value added tax credits	15,000
Reduced Brazil audit assessment for tax, penalties, and interest on recoverable value added tax credits	16,000
Santa Catarina [Member] | Minimum [Member]
Guarantees, Other Contingent Liabilities, and Other Matters [Line Items]
Estimate of possible loss on remaining VAT audit assessment	0
Santa Catarina [Member] | Maximum [Member]
Guarantees, Other Contingent Liabilities, and Other Matters [Line Items]
Estimate of possible loss on remaining VAT audit assessment	16,000
Parana [Member]
Guarantees, Other Contingent Liabilities, and Other Matters [Line Items]
Brazil audit assessment for tax, penalties, and interest on recoverable value added tax credits	18,000
Parana [Member] | Minimum [Member]
Guarantees, Other Contingent Liabilities, and Other Matters [Line Items]
Estimate of possible loss on remaining VAT audit assessment	0
Parana [Member] | Maximum [Member]
Guarantees, Other Contingent Liabilities, and Other Matters [Line Items]
Estimate of possible loss on remaining VAT audit assessment	$ 15,000