Employee Benefits Net Periodic Pension Costs (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
U.S. Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,752	$ 1,807	$ 2,113
Interest cost	4,289	4,782	4,879
Expected return on plan assets	(3,313)	(3,663)	(3,190)
Amortization of actuarial (gains) losses	1,509	914	1,066
Amortization of prior service (credit) cost	204	88	4
Curtailment loss (gain)	0	0	0
Special termination benefits	0	0	259
Effects of settlement	0	0	0
Net periodic pension cost	4,441	3,928	5,131
Non-U.S. Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	288	362	1,108
Interest cost	3,046	3,410	3,951
Expected return on plan assets	(2,945)	(2,859)	(2,567)
Amortization of actuarial (gains) losses	479	247	276
Amortization of prior service (credit) cost	16	16	19
Curtailment loss (gain)	(27)	(4,989)	0
Special termination benefits	45	956	1,012
Effects of settlement	0	0	(56)
Net periodic pension cost	$ 902	$ (2,857)	$ 3,743