Auction rate securities, at Fair Value

No definition available.

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- Definition

Description of the average credit rating indicative of likelihood of repayment of debt instruments given by credit rating agencies (for example, Standard and Poor's, Moody's, Fitch).

+ References

No definition available.

+ Details

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- Definition

Change in fair value of level 3 investment

+ References

No definition available.

+ Details

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- Definition

fair value input discounted cash flow term

+ References

No definition available.

+ Details

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- Definition

Financial Instruments Fair Value Assumptions Weighted Average Discount Rate

+ References

No definition available.

+ Details

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- Definition

The highest interest rate in the aggregated short-tem debt instruments.

+ References

No definition available.

+ Details

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- Definition

The lowest interest rate in the aggregated short-tem debt instruments.

+ References

No definition available.

+ Details

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- Definition

Joint Venture, Ownership Interest Percentage

+ References

No definition available.

+ Details

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- Definition

Number of Auction Rate Securities With Underlying Loans Which Have No Guarantees

+ References

No definition available.

+ Details

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- Definition

-- None. No documentation exists for this element. --

+ References

No definition available.

+ Details

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- Definition

Percentage of Loans Guaranteed

+ References

No definition available.

+ Details

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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- Details

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.

+ 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 210.5-02.2)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph g

-Article 7

+ Details

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- Details

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- Details

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Fair Value of Financial Assets and Liabilities - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
The rate used for the discount margin to determine the estimated fair value of investment in auction rate securities	1.00%
Short-term investments	$ 2,062us-gaap_ShortTermInvestments			$ 1,978us-gaap_ShortTermInvestments
Foreign debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale Securities	2,668			2,564
Average credit rating	A+
Foreign Sovereign Debt Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Average credit rating	AA+
Percentage of securities	3.00%
Auction rate securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale Securities	27			27
Average credit rating	AA
Change in fair value of level 3 investment	no material changes	no material changes
Number of auction rate securities	1
Auction rate securities that have partial guarantees by the U.S. government, market value	7
Percentage of loans guaranteed	95.00%
Coupon rate used to estimate fair value of investments - Start Range	0.00%
Coupon rate used to estimate fair value of investments - End Range	3.00%
Discount rate used to estimate fair value of investments	1.00%
The rate used for the discount margin to determine the estimated fair value of investment in auction rate securities				1.00%
Fair value input, discounted cash flow, term	5 years
Variable Rate Demand Note
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	$ 25
LenovoEMC [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Change in fair value of level 3 investment	no material changes	no material changes
Discount rate used to estimate fair value of investments			6.00%
Ownership percentage, joint venture	49.00%
Fair value input, discounted cash flow, term			3 years