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

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

v2.4.0.8
Operating Segment Information and Concentrations of Risk - Operating Segments and Geographical Information (Parenthetical) (Detail)
In Millions, unless otherwise specified
12 Months Ended
Mar. 31, 2014
USD ($)
Mar. 31, 2014
AUD
Mar. 31, 2013
USD ($)
Mar. 31, 2012
USD ($)
Mar. 31, 2014
General Corporate [Member]
USD ($)
Mar. 31, 2013
General Corporate [Member]
USD ($)
Mar. 31, 2012
General Corporate [Member]
USD ($)
Mar. 31, 2014
USA & Europe Fibre Cement [Member]
USD ($)
Mar. 31, 2013
USA & Europe Fibre Cement [Member]
USD ($)
Mar. 31, 2012
USA & Europe Fibre Cement [Member]
USD ($)
Mar. 31, 2014
Asia Pacific Fibre Cement [Member]
USD ($)
Mar. 31, 2013
Asia Pacific Fibre Cement [Member]
USD ($)
Mar. 31, 2012
Asia Pacific Fibre Cement [Member]
USD ($)
Mar. 31, 2014
Research and Development [Member]
USD ($)
Mar. 31, 2013
Research and Development [Member]
USD ($)
Mar. 31, 2012
Research and Development [Member]
USD ($)
Mar. 31, 2014
AICF [Member]
USD ($)
Mar. 31, 2013
AICF [Member]
USD ($)
Mar. 31, 2012
AICF [Member]
USD ($)
Segment Reporting Information [Line Items]                                      
Research and development costs $ 33.1   $ 37.2 $ 30.4       $ 9.6 $ 11.9 $ 10.1 $ 1.3 $ 1.7 $ 1.6 $ 22.2 $ 23.6 $ 18.7      
Selling, general and administrative expenses 224.4   218.6 191.0                   2.2 2.4 2.0      
Asset impairment      16.9 14.3       0 16.9 14.3                  
Unfavourable asbestos adjustments 195.8   117.1 15.8 195.8 117.1 15.8                        
AICF operating costs paid - non claims-handling 2.1 2.3 1.7 2.8                              
ASIC expenses     2.6 1.1                              
Net interest (expense) income (1.1)   2.4 (7.4)                         2.9 7.0 3.3
Value of Asbestos-related assets         812.4 882.8                          
Expenses related to legacy New Zealand product liability claims                     $ 1.7 $ 13.2 $ 5.4