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)

Stock-Based Compensation - Outstanding and Exercisable Options under 2001 Equity Incentive Plan and Long-Term Incentive Plan (Detail)

Stock-Based Compensation - Outstanding and Exercisable Options under 2001 Equity Incentive Plan and Long-Term Incentive Plan (Detail) (AUD)	12 Months Ended
	Mar. 31, 2013
Options Outstanding and Exercisable, Number	5,156,136
Options Outstanding and Exercisable, Aggregate Intrinsic Value	10,667,605
Weighted Average Exercise Price 5.99 [Member]
Options Outstanding and Exercisable, Number	285,750
Options Outstanding and Exercisable, Weighted Average Remaining Life	1 year 8 months 12 days
Options Outstanding and Exercisable, Weighted Average Exercise Price	5.99
Options Outstanding and Exercisable, Aggregate Intrinsic Value	1,148,715
Weighted Average Exercise Price 6.30 [Member]
Options Outstanding and Exercisable, Number	93,000
Options Outstanding and Exercisable, Weighted Average Remaining Life	1 year 10 months 24 days
Options Outstanding and Exercisable, Weighted Average Exercise Price	6.30
Options Outstanding and Exercisable, Aggregate Intrinsic Value	345,030
Weighted Average Exercise Price 6.38 [Member]
Options Outstanding and Exercisable, Number	624,254
Options Outstanding and Exercisable, Weighted Average Remaining Life	4 years 8 months 12 days
Options Outstanding and Exercisable, Weighted Average Exercise Price	6.38
Options Outstanding and Exercisable, Aggregate Intrinsic Value	2,266,042
Weighted Average Exercise Price 7.05 [Member]
Options Outstanding and Exercisable, Number	298,000
Options Outstanding and Exercisable, Weighted Average Remaining Life	8 months 12 days
Options Outstanding and Exercisable, Weighted Average Exercise Price	7.05
Options Outstanding and Exercisable, Aggregate Intrinsic Value	882,080
Weighted Average Exercise Price 7.83 [Member]
Options Outstanding and Exercisable, Number	932,502
Options Outstanding and Exercisable, Weighted Average Remaining Life	4 years 4 months 24 days
Options Outstanding and Exercisable, Weighted Average Exercise Price	7.83
Options Outstanding and Exercisable, Aggregate Intrinsic Value	2,032,854
Weighted Average Exercise Price 8.40 [Member]
Options Outstanding and Exercisable, Number	1,515,530
Options Outstanding and Exercisable, Weighted Average Remaining Life	3 years 7 months 6 days
Options Outstanding and Exercisable, Weighted Average Exercise Price	8.40
Options Outstanding and Exercisable, Aggregate Intrinsic Value	2,440,003
Weighted Average Exercise Price 8.90 [Member]
Options Outstanding and Exercisable, Number	1,392,100
Options Outstanding and Exercisable, Weighted Average Remaining Life	2 years 8 months 12 days
Options Outstanding and Exercisable, Weighted Average Exercise Price	8.90
Options Outstanding and Exercisable, Aggregate Intrinsic Value	1,545,231
Weighted Average Exercise Price 9.50 [Member]
Options Outstanding and Exercisable, Number	15,000
Options Outstanding and Exercisable, Weighted Average Remaining Life	2 years 10 months 24 days
Options Outstanding and Exercisable, Weighted Average Exercise Price	9.50
Options Outstanding and Exercisable, Aggregate Intrinsic Value	7,650
Exercise Price 7.94 [Member]
Options Outstanding and Exercisable, Weighted Average Remaining Life	3 years 3 months 18 days
Options Outstanding and Exercisable, Weighted Average Exercise Price	7.94