Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Leases, Capital
Assets acquired through capital leases	$ 3	$ 0	$ 0
Depreciation expense	32	42	50
Cash payments towards capital leases	32	40	41
Assets included in property, plant and equipment	137us-gaap_CapitalLeasedAssetsGross	168us-gaap_CapitalLeasedAssetsGross
Accumulated depreciation	108	109
Capital lease obligations:
2015	22
2016	2
2017	1
2018	1
2019	1
2020 and thereafter	7
Total minimum payments	34
Less: amount representing interest and executory costs	(8)
Present value of minimum payments	26
Less: current portion	(20)us-gaap_CapitalLeaseObligationsCurrent
Long-term portion	$ 6

Represents the amount of assets acquired through capital lease arrangements during the period.

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- Definition

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Article 5

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 30

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-Paragraph 1

-Subparagraph (b)

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Amount of minimum lease payments for capital leases.

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Amount of minimum lease payments for capital leases due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of minimum lease payments for capital leases due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of minimum lease payments for capital leases due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of minimum lease payments for capital leases due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount necessary to reduce net minimum lease payments to present value for capital leases.

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- Definition

Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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- Definition

The charge for the use of long-lived depreciable capital leased assets for the period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

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The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

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The cash outflow for the obligation for a lease meeting the criteria for capitalization (with maturities exceeding one year or beyond the operating cycle of the entity, if longer).

+ References

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