Significant Accounting Policies (Narrative) (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	9 Months Ended			9 Months Ended	12 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Jun. 30, 2013	Sep. 30, 2012	Jun. 30, 2013 Purification Solutions [Member]	Jun. 30, 2013 Service Life [Member]	Sep. 30, 2013 Subsequent Event [Member]	Sep. 30, 2013 Subsequent Event [Member] Service Life [Member]	Jun. 30, 2013 Buildings [Member] Minimum [Member]	Jun. 30, 2013 Buildings [Member] Maximum [Member]	Jun. 30, 2013 Machinery and Equipment [Member]	Jun. 30, 2013 Machinery and Equipment [Member] Previous Estimate [Member]	Jun. 30, 2013 Machinery and Equipment [Member] Service Life [Member]	Jun. 30, 2013 Machinery and Equipment [Member] Minimum [Member]	Jun. 30, 2013 Machinery and Equipment [Member] Maximum [Member]	Jun. 30, 2013 Other Fixed Assets [Member] Minimum [Member]	Jun. 30, 2013 Other Fixed Assets [Member] Maximum [Member]
Significant Accounting Policies [Line Items]
Royalty Agreement Contingent Payment Description	Quarterly royalty payments through fiscal year 2022
Change in life of Assets							20 years	25 years	25 years	10 years		10 years	25 years	3 years	25 years
Change in accounting estimate description											The Company changed the estimated depreciable lives of certain machinery and equipment from ten to twenty-five years to reflect the Company’s experience.
Increase in Income from continuing operations, estimated	$ 2
Increase in Income from continuing operations, expected					9
Change in income from continue operations				The change increased Income from continuing operations by $2 million ($0.03 per diluted common share).		The Company expects the change will increase Income from continuing operations by $9 million ($0.14 per diluted common share).
Increase in diluted common share, estimated	$ 0.03
Increase in diluted common share, expected					$ 0.14
Goodwill	499	480	462
Value of inventories under FIFO method	$ 53	$ 52