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

Asbestos - Additional Information (Detail)

Asbestos - Additional Information (Detail)					12 Months Ended
Asbestos - Additional Information (Detail)	Jul. 01, 2015 USD ($)	Jul. 01, 2015 AUD	Jul. 01, 2014 USD ($)	Jul. 01, 2014 AUD	Mar. 31, 2016 USD ($)	Mar. 31, 2016 AUD	Mar. 31, 2015 USD ($)	Mar. 31, 2013 USD ($)	Mar. 31, 2013 AUD	Jul. 02, 2012 USD ($)	Jul. 02, 2012 AUD	Apr. 02, 2012 USD ($)	Apr. 02, 2012 AUD	Mar. 31, 2012 USD ($)
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Line Items]
Discounted (but inflated) central estimate lower range value					$ 1,000,000,000	AUD 1,400,000,000
Discounted (but inflated) central estimate high range value					2,600,000,000	3,400,000,000
Undiscounted (but inflated) central estimate lower range value					1,300,000,000	1,700,000,000
Undiscounted (but inflated) central estimate high range value					3,600,000,000	4,700,000,000
Potential increase in discounted central estimate							30.00%
Contribution to AICF								$ 184,100,000	AUD 177,500,000	$ 45,400,000	AUD 45,200,000	$ 138,700,000	AUD 132,300,000	$ 0
Secured standby loan facility maximum borrowing capacity					$ 245,000,000	AUD 320,000,000
Secured standby loan Facility maturity date					Nov. 01, 2030
Loan facility, outstanding balance					$ 50,700,000		$ 13,600,000
Rate of interest of Benchmark Bonds					6.00%
Maturity date of Benchmark Bonds					May 01, 2020
AICF Funding [Member]
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Line Items]
Debt Instrument Periodic payment	$ 62,800,000	AUD 81,100,000	$ 113,000,000	AUD 119,900,000
Net cash provided by operating activities	$ 179,500,000		$ 322,800,000
Maximum percentage of Free Cash Flow contributed to AICF	35.00%	35.00%	35.00%	35.00%