Marketable Securities (current and non-current) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Marketable securities classification
Current marketable securities	$ 1,595	$ 1,461
Non-current marketable securities	1,031	896
Total marketable securities	2,626	2,357
U.S. government agency securities
Marketable securities classification
Current marketable securities	188	119
Non-current marketable securities	400	361
Foreign government agency securities
Marketable securities classification
Current marketable securities	3	8
Non-current marketable securities	31	15
Corporate debt securities
Marketable securities classification
Current marketable securities	455	413
Non-current marketable securities	364	255
Commercial paper
Marketable securities classification
Current marketable securities	254	30
Certificates of deposit/time deposits
Marketable securities classification
Current marketable securities	36	49
U.S. treasury securities
Marketable securities classification
Current marketable securities	20	0
Non-current marketable securities	17	34
U.S. municipal securities
Marketable securities classification
Current marketable securities	17	9
Non-current marketable securities	24	5
Asset-backed securities
Marketable securities classification
Current marketable securities	622	833
Non-current marketable securities	191	222
Asset-backed securities Automobile loan related
Marketable securities classification
Current marketable securities	453	530
Non-current marketable securities	159	188
Asset-backed securities Credit card related
Marketable securities classification
Current marketable securities	112	244
Non-current marketable securities	23	24
Asset-backed securities Equipment lease related
Marketable securities classification
Current marketable securities	56	54
Non-current marketable securities	9	10
Asset-backed securities Other asset-backed securities
Marketable securities classification
Current marketable securities	1	5
Auction rate securities
Marketable securities classification
Non-current marketable securities	$ 4	$ 4

Investments in debt and equity securities which are categorized neither as trading securities nor held-to-maturity securities and which are intended be sold or mature within one year from the balance sheet date or the normal operating cycle, whichever is 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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-Publisher FASB

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 3

-Section A

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+ Details

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

+ References+ Details

- Definition

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.

+ References

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

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+ Details