Cash and cash equivalents include all highly liquid investments with an original maturity, when purchased

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- Definition

Cost Method Investment, Ownership Percentage

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- Definition

Percentage Of Ownership Interests

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No definition available.

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- Definition

Percentage of restricted stock units granted, vested per year.

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No definition available.

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- Definition

Product warranty for a period

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- Definition

Recognizes the largest amount of the benefit that is greater realized upon ultimate settlement, percentage.

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No definition available.

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- Definition

The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 32

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16(a))

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- Definition

Interest rate stated in the contractual debt agreement.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a (1)

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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Summary of Significant Accounting Policies - Additional Information (Detail) In Thousands, except Share data, unless otherwise specified	12 Months Ended						12 Months Ended
	Mar. 31, 2013 USD ($)	Mar. 31, 2012 USD ($)	Mar. 31, 2013 2011 Senior Secured Revolving Credit Facility USD ($)	Mar. 31, 2013 China Term Loan due 2017 CNY	Mar. 31, 2013 India Term Loan due 2017 INR	Mar. 31, 2013 Senior Unsecured 3.375% Convertible Notes Due 2038 USD ($)	Mar. 31, 2013 Restricted Stock and Restricted Stock Units	Mar. 31, 2013 Minimum	Mar. 31, 2013 Minimum Reserve Power Batteries	Mar. 31, 2013 Minimum Motive Power Batteries	Mar. 31, 2013 Minimum Land, Buildings and Improvements	Mar. 31, 2013 Minimum Machinery and Equipment	Mar. 31, 2013 Maximum	Mar. 31, 2013 Maximum Reserve Power Batteries	Mar. 31, 2013 Maximum Motive Power Batteries	Mar. 31, 2013 Maximum Land, Buildings and Improvements	Mar. 31, 2013 Maximum Machinery and Equipment
Summary Of Significant Accounting Policies [Line Items]
Percentage of investment ownership, consolidated								50.00%
Percentage of investment ownership, equity method								20.00%					50.00%
Percentage of investment ownership, cost method													20.00%
Product warranty for a period									1 year	1 year				20 years	7 years
Cash and cash equivalents include all highly liquid investments with an original maturity, when purchased, in months	3 months
Property, plant, and equipment, useful life											10 years	3 years				33 years	15 years
Estimated useful lives of finite-lived assets								3 years					20 years
Fair value of Company's new senior secured revolving credit facility			$ 350,000	75,000	273,780
Convertible Notes	$ 172,500	$ 172,500				$ 172,500
Interest rate of debt instrument						3.375%
Recognizes the largest amount of the benefit that is greater realized upon ultimate settlement, percentage	50.00%
Market share units converted into common stock for each unit								0					2
Percentage of restricted stock units granted, vested per year							25.00%
Vesting period, in years							4 years