Change in Accounting Principles (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended
Jan. 01, 2015	Mar. 31, 2015	Dec. 31, 2014
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage of consolidated inventories impacted by change in accounting principle	0.36
Inventories		$ 12,231us-gaap_InventoryNet	$ 11,930us-gaap_InventoryNet
Retained earnings		32,667	31,849
Inventory valuation methodology adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Inventories	(7)
Current deferred tax asset	3
Retained earnings	4
Effect of change on net income	$ 4

Represents the percentage of consolidated inventories impacted by change in accounting principle

No definition available.

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- Definition

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, netted by jurisdiction and classified as current.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 45

-Paragraph 4

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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

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a))

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- Definition

Amount of the effect of a change in accounting principle on net income.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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