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Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Mar. 31, 2015
Accounting Policies [Abstract] |
Schedule of Exchange Rates Used to Convert Australian Dollar into US Dollars | Unless otherwise noted, the exchange rates used to convert Australian dollar denominated amounts into US dollars in the consolidated financial statements are as follows:
|  | 31 March |
(US$1 = A$) |  | 2015 |  |  | 2014 |  |  | 2013 |
Assets and liabilities |  |  | 1.3096 |  |  |  | 1.0845 |  |  |  | 0.9597 |
Statements of operations |  |  | 1.1419 |  |  |  | 1.0716 |  |  |  | 0.9694 |
Cash flows - beginning cash |  |  | 1.0845 |  |  |  | 0.9597 |  |  |  | 0.9614 |
Cash flows - ending cash |  |  | 1.3096 |  |  |  | 1.0845 |  |  |  | 0.9597 |
Cash flows - current period movements |  |  | 1.1419 |  |  |  | 1.0716 |  |  |  | 0.9694 |
Property, Plant and Equipment Estimated Useful Lives | Depreciation of property, plant and equipment is computed using the straight-line method over the following estimated useful lives:
|  | Years |
Buildings |  |  | 40 |
Building improvements |  |  | 5 to 40 |
Manufacturing machinery |  |  | 10 to 20 |
General equipment |  |  | 5 to 10 |
Computer equipment, software, and software development |  |  | 3 to 7 |
Office furniture and equipment |  |  | 3 to 10 |
Basic and Dilutive Common Shares Outstanding Used in Determining Net Income Per Share | Accordingly, basic and dilutive common shares outstanding used in determining net income per share are as follows:
|  | Years Ended 31 March |
(Millions of shares) |  | 2015 |  |  | 2014 |  |  | 2013 |
Basic common shares outstanding |  |  | 445.0 |  |  |  | 442.6 |  |  |  | 439.2 |
Dilutive effect of stock awards |  |  | 1.4 |  |  |  | 2.0 |  |  |  | 1.4 |
Diluted common shares outstanding |  |  | 446.4 |  |  |  | 444.6 |  |  |  | 440.6 |
(US dollars) |  | 2015 |  |  | 2014 |  |  | 2013 |
Net income per share - basic |  | $ | 0.65 |  |  | $ | 0.22 |  |  | $ | 0.10 |
Net income per share - diluted |  | $ | 0.65 |  |  | $ | 0.22 |  |  | $ | 0.10 |

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- Definition Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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