Acquisition of NHUMO - Components and Allocation of Purchase Price (Detail) (USD $) In Millions, unless otherwise specified				1 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012	Oct. 31, 2013 Norit N.V. [Member]	Sep. 30, 2014 Norit N.V. [Member]	Sep. 30, 2014 Norit N.V. [Member] Measurement Period Adjustments [Member]
Assets
Cash				$ 7	$ 7
Accounts receivable				33	33
Inventories				14	14
Property, plant and equipment				48	48
Other non-current assets				1	1
Intangible assets				57	63	6
Goodwill	536	502	478	51	45	(6)
Total assets acquired				211	211
Liabilities
Accounts payable, accruals and other liabilities				(18)	(20)	(2)
Deferred tax liabilities - long term				(31)	(29)	2
Total liabilities assumed				(49)	(49)
Net assets acquired				162	162
Cash consideration paid				80
Fair value of redeemable preferred stock	27	0		28
Previously held equity interest in NHUMO				54
Total				$ 162