Commitments Contingencies and Litigation - Additional Information (Detail) In Thousands, unless otherwise specified	12 Months Ended										12 Months Ended
	Mar. 31, 2013 USD ($) Person	Mar. 31, 2012 USD ($)	Oct. 02, 2011 USD ($)	Oct. 02, 2011 EUR (€)	Mar. 31, 2009 USD ($)	Mar. 31, 2009 EUR (€)	Mar. 31, 2013 Lead hedge forward contracts USD ($) lb	Mar. 31, 2012 Lead hedge forward contracts USD ($) lb	Mar. 31, 2013 Foreign currency forward contracts USD ($)	Mar. 31, 2012 Foreign currency forward contracts USD ($)	Mar. 31, 2013 Interest rate swap agreements USD ($)	Mar. 31, 2012 Interest rate swap agreements USD ($)
Commitments, Contingencies And Litigation [Line Items]
Litigation damages assessed and paid					$ 4,200	€ 2,700
Refund from damages paid			900	671
Reserves of environmental liabilities	2,915	2,995
Company number of employees	9,000
Percentage of employees covered by collective bargaining agreements	35.00%
Average term of collective bargaining agreements	2 years
Longest term of collective bargaining agreements	4 years
Percentage of collective bargaining agreements that expire in next twelve months	33.00%
Purchase price of hedges, pounds of lead							56,300,000	60,000,000
Purchase price of hedges							56,601	56,610	73,115	53,531
Convertible interest rate swap											$ 65,000	$ 85,000
Interest rate swap agreements expiration date											May 01, 2013