Marketable Securities (current and non-current) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Marketable securities classification
Current marketable securities	$ 153	$ 626
Non-current marketable securities	13	828
Total marketable securities	166	1,454
U.S. government agency securities
Marketable securities classification
Current marketable securities		67
Non-current marketable securities	1	41
Foreign government agency securities
Marketable securities classification
Current marketable securities	10	75
Non-current marketable securities		20
Corporate debt securities
Marketable securities classification
Current marketable securities	11	241
Non-current marketable securities		378
Commercial paper
Marketable securities classification
Current marketable securities	25
Certificates of deposit/time deposits
Marketable securities classification
Current marketable securities	34	41
U.S. treasury securities
Marketable securities classification
Non-current marketable securities		38
U.S. municipal securities
Marketable securities classification
Current marketable securities	3
Non-current marketable securities	12	15
Asset-backed securities
Marketable securities classification
Current marketable securities	70	202
Non-current marketable securities		336
Asset-backed securities Automobile loan related
Marketable securities classification
Current marketable securities	38	122
Non-current marketable securities		160
Asset-backed securities Credit card related
Marketable securities classification
Current marketable securities	10	59
Non-current marketable securities		103
Asset-backed securities Equipment lease related
Marketable securities classification
Current marketable securities	3	21
Non-current marketable securities		27
Asset-backed securities Other asset-backed securities
Marketable securities classification
Current marketable securities	$ 19
Non-current marketable securities		$ 46

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

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

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Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

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

-Publisher FASB

-Name Accounting Standards Codification

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