James Hardie Industries plc Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Operating Segment Information and Concentrations of Risk - Operating Segments and Geographical Information (Parenthetical) (Detail)

v2.4.0.6

Operating Segment Information and Concentrations of Risk - Operating Segments and Geographical Information (Parenthetical) (Detail) In Millions, unless otherwise specified	12 Months Ended
	Mar. 31, 2013 USD ($)	Mar. 31, 2013 AUD	Mar. 31, 2012 USD ($)	Mar. 31, 2011 USD ($)	Mar. 31, 2013 USA and Europe Fibre Cement [Member] USD ($)	Mar. 31, 2012 USA and Europe Fibre Cement [Member] USD ($)	Mar. 31, 2011 USA and Europe Fibre Cement [Member] USD ($)	Mar. 31, 2013 Asia Pacific Fibre Cement [Member] USD ($)	Mar. 31, 2012 Asia Pacific Fibre Cement [Member] USD ($)	Mar. 31, 2011 Asia Pacific Fibre Cement [Member] USD ($)	Mar. 31, 2013 Research and Development [Member] USD ($)	Mar. 31, 2012 Research and Development [Member] USD ($)	Mar. 31, 2011 Research and Development [Member] USD ($)	Mar. 31, 2013 General Corporate [Member] USD ($)	Mar. 31, 2012 General Corporate [Member] USD ($)	Mar. 31, 2011 General Corporate [Member] USD ($)	Mar. 31, 2013 AICF [Member] USD ($)	Mar. 31, 2012 AICF [Member] USD ($)	Mar. 31, 2011 AICF [Member] USD ($)
Segment Reporting Information [Line Items]
Research and development costs	$ 37.2		$ 30.4	$ 28.0	$ 11.9	$ 10.1	$ 9.7	$ 1.7	$ 1.6	$ 1.4	$ 23.6	$ 18.7	$ 16.9
Selling, general and administrative expenses	218.6		191.0	173.4							2.4	2.0	3.2
Asset impairments	16.9		14.3		16.9	14.3
Unfavorable asbestos adjustments	117.1		15.8	85.8										117.1	15.8	85.8
AICF operating costs paid - non claims-handling	1.7	1.6	2.8	2.2
ASIC expenses (benefit), net	2.6		1.1	(8.7)
Net interest (expense) income	2.4		(7.4)	(4.4)													7.0	3.3	4.3
Value of Asbestos-related assets														882.8	825.2
Increase to provision for New Zealand product liability claims	$ 13.2							$ 13.2	$ 5.4	$ 1.4

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AICF operating cost paid non claim handling.

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Comprised of changes in actuarial estimates received as of March 31 each year and the effect of foreign exchange movements in the asbestos related assets and liabilities which are denominated in Australian dollars.

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The net amount of Australian Securities and Investments Commission expense (recoveries).

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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The net amount of operating interest income (expense).

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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