Inventories (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Inventories
Net carrying values of inventories valued under the LIFO method	$ 199us-gaap_LIFOInventoryAmount	$ 205us-gaap_LIFOInventoryAmount
Raw materials	71us-gaap_InventoryRawMaterials	74us-gaap_InventoryRawMaterials
Materials and supplies	585us-gaap_OtherInventorySupplies	628us-gaap_OtherInventorySupplies
Finished goods	485us-gaap_InventoryFinishedGoods	589us-gaap_InventoryFinishedGoods
Inventories, Gross	1,141us-gaap_InventoryGross	1,291us-gaap_InventoryGross
LIFO reserve	(89)us-gaap_InventoryLIFOReserve	(91)us-gaap_InventoryLIFOReserve
Total	$ 1,052us-gaap_InventoryNet	$ 1,200us-gaap_InventoryNet

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a)(1))

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

+ References

+ Details

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Amount of difference between inventory at lower of LIFO cost or market and inventory at lower of other inventory accounting method cost or market, for example, but not limited to, FIFO or average cost.

+ References

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section S99

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-Subparagraph (SX 210.5-02.6(a))

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 330

-SubTopic 10

-Section 35

-Paragraph 2

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or 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 6

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-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Subparagraph (SX 210.5-02.6(a)(4))

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The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or 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 6

-Subparagraph a

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Glossary Inventory

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