Employee Benefits Amounts Showing in Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Prior service credit (cost)	$ 2,400	$ 5,457
Net actuarial losses	(48,188)	(36,341)
Deferred taxes	10,037	10,457
Balance at	(20,427)
Prior service credit (cost)	(3,057)
Net actuarial losses	(11,847)
Deferred taxes	(420)
Balance at	(15,324)
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax	(35,751)
U.S. and Non-U.S. Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Prior service credit (cost)	(2,413)	(1,041)
Net actuarial losses	(41,674)	(30,632)
Deferred taxes	10,572	11,127
Balance at	(20,546)
Prior service credit (cost)	(1,372)
Net actuarial losses	(11,042)
Deferred taxes	(555)
Balance at	(12,969)
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax	(33,515)
U.S. and Non-U.S. Post-retirement [Member]
Defined Benefit Plan Disclosure [Line Items]
Prior service credit (cost)	4,813	6,498
Net actuarial losses	(6,514)	(5,709)
Deferred taxes	(535)	(670)
Balance at	119
Prior service credit (cost)	(1,685)
Net actuarial losses	(805)
Deferred taxes	135
Balance at	(2,355)
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax	$ (2,236)