Derivative Financial Instruments - Effect of Derivative Instruments on Consolidated Condensed Statements of Income (Detail) - Designated as Hedging Instrument - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in AOCI on Derivatives (Effective Portion)	$ 8,752	$ (6,384)	$ 463
Gain (Loss) Reclassified from AOCI (Effective Portion)	6,236	(7,144)	(2,961)
Lead hedge forward contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in AOCI on Derivatives (Effective Portion)	7,907	(3,361)	(7,743)
Foreign currency forward contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in AOCI on Derivatives (Effective Portion)	845	(3,023)	8,206
Cost of Sales \| Lead hedge forward contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Reclassified from AOCI (Effective Portion)	5,803	(11,085)	(4,347)
Cost of Sales \| Foreign currency forward contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Reclassified from AOCI (Effective Portion)	$ 433	$ 3,941	$ 1,386

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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+ References

No definition available.

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