v2.4.0.6

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 |

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