Income Taxes Income Tax Provision (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Income Tax Contingency [Line Items]
U.S.	$ (44,731)	$ (21,923)	$ (51,092)
Non-U.S.	95,798	76,081	83,941
Income before income taxes and other items	51,067	54,158	32,849
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current, Federal	(2,723)	0	472
Current, State	0	0	0
Current, Non-U.S.	5,999	31,798	7,346
Current income tax expense (benefit)	3,276	31,798	7,818
Deferred, Federal	3,466	0	97,311
Deferred, State	0	0	631
Deferred, Non-U.S.	21,250	(6,759)	1,700
Deferred, income tax expense (benefit)	24,716	(6,759)	99,642
Total	27,992	25,039	107,460
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Tax expense at U.S. statutory rate	17,873	18,955	11,497
Effect of non-U.S. income taxes	(1,921)	(4,712)	(7,322)
Goodwill amortization	0	0	(4,640)
Change in valuation allowance	26,598	1,617	111,679
Increase (decrease) in reserves for uncertain tax positions	(11,781)	3,452	4,489
Exchange effects and currency translation	(1,482)	3,958	(7,120)
Permanent items	(1,295)	1,769	(1,123)
Total	$ 27,992	$ 25,039	$ 107,460