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Property, Plant and Equipment - Components of Property, Plant and Equipment (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Mar. 31, 2015
Property Plant And Equipment Capitalized Interest Costs [Abstract]
Capitalized interest	$ 1.7us-gaap_InterestPaidCapitalized

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- Definition

The amount of cash paid during the current period for interest that is capitalized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

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