Income Taxes Level 4 (Details) - Deferred Tax Assets and Liabilities (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Assets
Non-pension post-employment	$ 8	$ 9
Accrued and other expenses	91	74
Deferred Tax Assets, Property, Plant and Equipment	3	2
Loss and credit carryforwards	647	615
Pension and postretirement benefit liabilities	58msc_DeferredTaxAssetPensionLiabilities	39msc_DeferredTaxAssetPensionLiabilities
Gross deferred tax assets	815us-gaap_DeferredTaxAssetsGross	748us-gaap_DeferredTaxAssetsGross
Valuation allowance	(588)	(518)	(122)	(432)
Net deferred tax asset	227	230
Liabilities [Abstract]
Property, plant and equipment	(119)	(125)
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Pensions	0	5
Unrepatriated earnings of foreign subsidiaries	(73)	(65)
Intangible assets	(25)	(28)
Gross deferred tax liabilities	(217)us-gaap_DeferredIncomeTaxLiabilities	(223)us-gaap_DeferredIncomeTaxLiabilities
Net deferred tax asset	$ 10us-gaap_DeferredTaxLiabilities	$ 7us-gaap_DeferredTaxLiabilities

Deferred Tax Asset - Pension Liabilities

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- Definition

Gross Deferred Tax Asset, Net of Valuation Allowance

+ References

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Amount of deferred tax liability attributable to taxable temporary differences.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Deferred Tax Liability

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment.

+ References

No definition available.

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from pension benefits.

+ References

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from postretirement benefits.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences net of deferred tax asset attributable to deductible temporary differences and carryforwards after valuation allowances.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiaries and other recognized entities not within the country of domicile of the entity.

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