Restructuring - Additional Information (Detail)				1 Months Ended	3 Months Ended		6 Months Ended		78 Months Ended
	Nov. 11, 2015 Employees	Oct. 20, 2015 Position	Apr. 26, 2013 Employees	Jan. 31, 2014 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)
Restructuring Cost And Reserve [Line Items]
Other charges						$ 3,000,000
Restructuring costs in accrued expenses					$ 13,000,000		$ 13,000,000		$ 13,000,000	$ 22,000,000	$ 9,000,000
Restructuring Activities Other [Member]
Restructuring Cost And Reserve [Line Items]
Pre-tax charge to earnings							1,000,000	$ 4,000,000
Severance and Employee Benefits [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring costs in accrued expenses					11,000,000		11,000,000		11,000,000	19,000,000	5,000,000
Environmental Remediation [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring costs in accrued expenses					2,000,000		2,000,000		2,000,000	$ 2,000,000	$ 2,000,000
Maximum [Member]
Restructuring Cost And Reserve [Line Items]
Benefit					1,000,000
Maximum [Member] | Restructuring Activities Other [Member]
Restructuring Cost And Reserve [Line Items]
Additional restructuring charges remainder of fiscal 2016 and thereafter							1,000,000
Maximum [Member] | Severance Costs [Member] | Restructuring Activities Other [Member]
Restructuring Cost And Reserve [Line Items]
Accrued severance charges					1,000,000		1,000,000		1,000,000
Operational Restructuring [Member]
Restructuring Cost And Reserve [Line Items]
Number of positions eliminated | Position		300
Pre-tax charge to earnings					2,000,000		26,000,000
Additional restructuring charges through the reminder of fiscal 2016							2,000,000
Expected cumulative net cash outlays related to plan					29,000,000		29,000,000		29,000,000
Cash payments							18,000,000
Restructuring cash payments through the reminder of fiscal 2016							9,000,000
Restructuring cash payments, thereafter							2,000,000
Operational Restructuring [Member] | Severance Costs [Member]
Restructuring Cost And Reserve [Line Items]
Accrued severance charges					8,000,000		8,000,000		8,000,000
Operational Restructuring [Member] | Maximum [Member]
Restructuring Cost And Reserve [Line Items]
Additional restructuring charges after current fiscal							1,000,000
Closure of Carbon Black Facility [Member]
Restructuring Cost And Reserve [Line Items]
Pre-tax charge to earnings							25,000,000
Expected cumulative net cash outlays related to plan					8,000,000		8,000,000		8,000,000
Cash payments							2,000,000
Restructuring cash payments through the reminder of fiscal 2016							6,000,000
Affected employees | Employees	50
Site demolition and other miscellaneous costs through the remainder of fiscal 2016							5,000,000
Severance charges							2,000,000
Other charges							1,000,000
Severance and other charges							1,000,000
Closure of Carbon Black Facility [Member] | Severance Costs [Member]
Restructuring Cost And Reserve [Line Items]
Accrued severance charges					1,000,000		1,000,000		1,000,000
Closure of Carbon Black Facility [Member] | Asset Impairment and Accelerated Depreciation [Member]
Restructuring Cost And Reserve [Line Items]
Pre-tax charge to earnings					1,000,000		23,000,000
Closure of Carbon Black Facility [Member] | Severance and Employee Benefits [Member]
Restructuring Cost And Reserve [Line Items]
Pre-tax charge to earnings							2,000,000
Shared Service Center Transition [Member]
Restructuring Cost And Reserve [Line Items]
Pre-tax charge to earnings				$ 24,000,000			0	5,000,000
Cash payments							20,000,000
Severance charges				16,000,000			13,000,000	1,000,000
Other charges				$ 8,000,000			7,000,000	4,000,000
Expected severance charges					1,000,000		1,000,000		1,000,000
Restructuring costs in accrued expenses					1,000,000		1,000,000		1,000,000
Closure of Port Dickson [Member]
Restructuring Cost And Reserve [Line Items]
Pre-tax charge to earnings							19,000,000
Affected employees | Employees			90
Severance charges							2,000,000
Other charges							1,000,000
Net pre-tax gain							1,000,000
Accelerated depreciation and asset write-offs							16,000,000
Site demolition, clearing and environmental remediation costs							2,000,000
Expected cumulative net cash received to this plan					3,000,000		$ 3,000,000		$ 3,000,000
Closure of Port Dickson [Member] | Land [Member]
Restructuring Cost And Reserve [Line Items]
Gain on sale of asset					$ 2,000,000
Closure of Port Dickson [Member] | Cabot [Member]
Restructuring Cost And Reserve [Line Items]
Equity share in CMSB			50.10%
Closure of Port Dickson [Member] | CMSB [Member]
Restructuring Cost And Reserve [Line Items]
Portion of the charges that are allocable to the noncontrolling interest					49.90%		49.90%		49.90%
Closure of Port Dickson [Member] | Severance and Employee Benefits [Member]
Restructuring Cost And Reserve [Line Items]
Expected cumulative net cash received to this plan					$ 2,000,000		$ 2,000,000		$ 2,000,000
Closure of Port Dickson [Member] | Asset Sales [Member]
Restructuring Cost And Reserve [Line Items]
Expected cumulative net cash received to this plan					7,000,000		7,000,000		7,000,000
Closure of Port Dickson [Member] | Environmental Remediation [Member]
Restructuring Cost And Reserve [Line Items]
Expected cumulative net cash received to this plan					1,000,000		1,000,000		1,000,000
Closure of Port Dickson [Member] | Facility Closure Costs [Member]
Restructuring Cost And Reserve [Line Items]
Expected cumulative net cash received to this plan					1,000,000		1,000,000		1,000,000
Closure of Port Dickson [Member] | Maximum [Member]
Restructuring Cost And Reserve [Line Items]
Pre-tax charge to earnings					1,000,000	1,000,000	1,000,000	1,000,000
Restructuring cash payments through the reminder of fiscal 2016							1,000,000
Restructuring costs in accrued expenses					1,000,000		1,000,000		1,000,000
Previous Actions and Sites Pending Sale [Member]
Restructuring Cost And Reserve [Line Items]
Pre-tax charge to earnings								$ 2,000,000
Cash payments									78,000,000
Severance charges					67,000,000				63,000,000
Other charges					23,000,000				24,000,000
Expected severance charges					158,000,000		158,000,000		158,000,000
Net pre-tax gain							7,000,000
Gain on sale of asset					8,000,000
Site demolition, clearing and environmental remediation costs					10,000,000				10,000,000
Restructuring accelerated depreciation and asset impairments					66,000,000
Proceeds from sale of Assets									19,000,000
Previous Actions and Sites Pending Sale [Member] | Land Rights [Member]
Restructuring Cost And Reserve [Line Items]
Gain on sale of asset					7,000,000
Previous Actions and Sites Pending Sale [Member] | Severance Costs [Member] | Restructuring Activities Other [Member]
Restructuring Cost And Reserve [Line Items]
Accrued severance charges					$ 2,000,000		2,000,000		$ 2,000,000
Previous Actions and Sites Pending Sale [Member] | Environmental and Other Closure Related Costs [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring cash payments through the reminder of fiscal 2016 and thereafter							$ 2,000,000
Previous Actions and Sites Pending Sale [Member] | Maximum [Member]
Restructuring Cost And Reserve [Line Items]
Pre-tax charge to earnings						$ 1,000,000