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Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Mar. 31, 2016 | Sep. 30, 2015
Significant Accounting Policies [Line Items] |  |
Value of inventories under FIFO method | $ 26 | $ 30
Buildings [Member] | Minimum [Member] |  |
Significant Accounting Policies [Line Items] |  |
Useful life of property, plant and equipment | 20 years |
Buildings [Member] | Maximum [Member] |  |
Significant Accounting Policies [Line Items] |  |
Useful life of property, plant and equipment | 25 years |
Machinery and Equipment [Member] | Minimum [Member] |  |
Significant Accounting Policies [Line Items] |  |
Useful life of property, plant and equipment | 10 years |
Machinery and Equipment [Member] | Maximum [Member] |  |
Significant Accounting Policies [Line Items] |  |
Useful life of property, plant and equipment | 25 years |
Other Fixed Assets [Member] | Minimum [Member] |  |
Significant Accounting Policies [Line Items] |  |
Useful life of property, plant and equipment | 3 years |
Other Fixed Assets [Member] | Maximum [Member] |  |
Significant Accounting Policies [Line Items] |  |
Useful life of property, plant and equipment | 25 years |

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- Definition Significant accounting policies. + References No definition available. + Details
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- Definition The excess of replacement or current cost over the stated LIFO (last in first out) inventory value when the LIFO inventory method is utilized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(c)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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