Income Taxes Accounting for Uncertainty in Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2010
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at	$ 9,019	$ 9,004	$ 20,129
Increases for current year tax positions	58	3,500	2,292
Increases (reductions) for prior year tax positions	3,030	5,539	(1,698)
Impact of changes in exchange rates	(303)	(63)	3,664
Reductions for settlements	0	(8,961)	(15,383)
Balance at	11,804	9,019	9,004
Unrecognized tax benefits, income tax penalties and interest accrued	1,176	2,446
Unrecognized tax benefits, interest on income taxes accrued	8,690	7,780
Unrecognized tax benefits, income tax penalties accrued	1,190	1,434
Unrecognized tax benefits, income tax penalties and interest expense, related to settlements		307
Unrecognized tax benefits, income tax penalties and interest expense, related to expiration of statue of limitations		203
Unrecognized tax benefits including interest and taxes	21,683	18,233
Unrecognized tax benefits, increases resulting from settlements	307
Unrecognized tax benefits, reductions resulting from lapse of applicable statute of limitations	355
Increase for current year tax positions	4,112
Non-U.S [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, interest on income taxes accrued		7,789
Unrecognized tax benefits, income tax penalties accrued		343
Unrecognized tax benefits, reductions resulting from lapse of applicable statute of limitations	$ 1,359
Non-U.S [Member] | Minimum [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Income Tax Examination, Open Tax Years	3 years
Non-U.S [Member] | Maximum [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Income Tax Examination, Open Tax Years	6 years
State [Member] | Minimum [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Income Tax Examination, Open Tax Years	3 years
State [Member] | Maximum [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Income Tax Examination, Open Tax Years	6 years