v3.7.0.1

Summary of Significant Accounting Policies - Additional Information (Detail) | 12 Months Ended
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Mar. 31, 2017 segment shares
Summary Of Significant Accounting Policies [Line Items] |
Cash and cash equivalents include all highly liquid investments with an original maturity, when purchased, in months | 3 months
Number of geographical regions | segment | 3
Restricted Stock and Restricted Stock Units |
Summary Of Significant Accounting Policies [Line Items] |
Percentage of restricted stock units granted, vested per year | 25.00%
Vesting period, in years | 4 years
Minimum |
Summary Of Significant Accounting Policies [Line Items] |
Percentage of investment ownership, consolidated | 50.00%
Percentage of investment ownership, equity method | 20.00%
Estimated useful lives of finite-lived assets | 3 years
Market share units converted into common stock for each unit | 0
Minimum | Reserve Power Batteries |
Summary Of Significant Accounting Policies [Line Items] |
Product warranty for a period | 1 year
Minimum | Motive Power Batteries |
Summary Of Significant Accounting Policies [Line Items] |
Product warranty for a period | 1 year
Minimum | Building and Improvements |
Summary Of Significant Accounting Policies [Line Items] |
Property, plant, and equipment, useful life | 10 years
Minimum | Machinery and Equipment |
Summary Of Significant Accounting Policies [Line Items] |
Property, plant, and equipment, useful life | 3 years
Maximum |
Summary Of Significant Accounting Policies [Line Items] |
Percentage of investment ownership, equity method | 50.00%
Percentage of investment ownership, cost method | 20.00%
Estimated useful lives of finite-lived assets | 20 years
Market share units converted into common stock for each unit | 2
Maximum | Reserve Power Batteries |
Summary Of Significant Accounting Policies [Line Items] |
Product warranty for a period | 20 years
Maximum | Motive Power Batteries |
Summary Of Significant Accounting Policies [Line Items] |
Product warranty for a period | 7 years
Maximum | Building and Improvements |
Summary Of Significant Accounting Policies [Line Items] |
Property, plant, and equipment, useful life | 33 years
Maximum | Machinery and Equipment |
Summary Of Significant Accounting Policies [Line Items] |
Property, plant, and equipment, useful life | 15 years

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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 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586 + Details
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