Number of claimants in pending cases asserting claims in connection with respiratory products.

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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The aggregate amount disbursed during the reporting period to settle environmental loss contingencies.

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Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

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Amount of payments made reducing loss contingency liability.

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Commitments and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2014 claimants	Dec. 31, 2013	Sep. 30, 2014 claimants	Sep. 30, 2013
Environmental Matters [Member]
Loss Contingencies [Line Items]
Reserved for environmental matters, on an undiscounted basis	$ 17		17
Respirator Liabilities [Member]
Loss Contingencies [Line Items]
Number of claimants	41,000		41,000
Respirator reserve on discounted basis	12			13
Cash payments for respirator reserves	1	2
Maximum [Member] \| Environmental Matters [Member]
Loss Contingencies [Line Items]
Cash payments for environmental reserves	$ 1	$ 1