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 with less than AA+ 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.

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This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

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This item represents the gross unrealized losses for securities which are categorized neither as held-to-maturity nor trading securities. Such gross unrealized losses are the excess of the carrying value of the Available-for-sale Securities over their fair value as of the reporting date. Such gross unrealized losses are included in other comprehensive income in the statement of shareholders' equity, 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 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 costs basis.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 12
-Subparagraph b

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 21
-Subparagraph a

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 19

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale which are intended to be held for less than one year or the normal operating cycle, whichever is longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 2
-Article 5

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Total debt and equity financial instruments including: (1) securities held-to-maturity and (2) securities available-for-sale that will be held for the long-term.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 17

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Marketable Securities (Detail) (USD $)	12 Months Ended
Marketable Securities (Detail) (USD $)	Dec. 31, 2009	Dec. 31, 2008	Dec. 31, 2010
Marketable securities classification
Current marketable securities	$ 744,000,000		$ 1,101,000,000
Non-current marketable securities	825,000,000		540,000,000
Total marketable securities	1,569,000,000		1,641,000,000
Gross unrealized losses on marketable securities (pre-tax)	12,000,000		9,000,000
Gross unrealized gains on marketable securities (pre-tax)	3,000,000		5,000,000
Gross realized gains on sales or maturities of marketable securities		5,000,000
Gross realized losses on sales or maturities of marketable securities	3,000,000
Estimated fair value of auction rate securities			592,000,000
Fair market value of securities rated AA+			2,000,000
Number of fair market value of securities rated AA+			2
U.S. government agency securities
Marketable securities classification
Current marketable securities	326,000,000		246,000,000
Non-current marketable securities	165,000,000		63,000,000
Foreign government agency securities
Marketable securities classification
Current marketable securities			52,000,000
Non-current marketable securities			3,000,000
Corporate debt securities
Marketable securities classification
Current marketable securities	154,000,000		280,000,000
Non-current marketable securities	112,000,000		192,000,000
U.S. dollar commercial paper
Marketable securities classification
Current marketable securities			55,000,000
U.S. treasury securities
Marketable securities classification
Current marketable securities			55,000,000
Non-current marketable securities	94,000,000		44,000,000
U.S. municipal securities
Marketable securities classification
Current marketable securities			20,000,000
Non-current marketable securities			3,000,000
Asset-backed securities
Marketable securities classification
Current marketable securities	256,000,000		364,000,000
Non-current marketable securities	449,000,000		228,000,000
Asset-backed securities Automobile loan related
Marketable securities classification
Current marketable securities	198,000,000		253,000,000
Non-current marketable securities	317,000,000		144,000,000
Asset-backed securities Credit card related
Marketable securities classification
Current marketable securities	9,000,000		79,000,000
Non-current marketable securities	98,000,000		70,000,000
Asset-backed securities Equipment lease related
Marketable securities classification
Current marketable securities	41,000,000		24,000,000
Non-current marketable securities	29,000,000		14,000,000
Asset-backed securities Other
Marketable securities classification
Current marketable securities	8,000,000		8,000,000
Non-current marketable securities	5,000,000
Auction rate securities
Marketable securities classification
Non-current marketable securities	5,000,000		7,000,000
Gross unrealized losses on marketable securities (pre-tax)	8,000,000		6,000,000
Estimated fair value of auction rate securities	5,000,000		7,000,000
Other securities
Marketable securities classification
Current marketable securities	$ 8,000,000		$ 29,000,000