Stock-Based Compensation (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 162	$ 151	$ 332	$ 320
Income tax benefits	(59)	(55)	(120)	(117)
Total Stock-based compensation cost	104	96	212	203
Stock-based compensation cost, increase (decrease) related to the company's assumption of stock-based awards previously issued by acquired entities	8		19
Stock-based compensation cost, increase (decrease) due to stock options, restricted and performance-based stock units	4		(9)
Stock-based compensation cost, unrecognized, related to non-vested awards.	1,668		1,668
Stock-based compensation cost, unrecognized, related to non-vested awards, weighted-average period of recognition (in years)			3.1
Cost
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	22	24	46	49
Selling, general and administrative
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	126	116	256	249
Research, development and engineering
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	14	12	30	24
Other (income) and expense
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost		$ (1)		$ (1)

The change in the pre-tax stock-based compensation cost from the corresponding period in the prior year, due to stock options, restricted and performance-based stock units.

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- Definition

Represents the change in the pre-tax stock-based compensation cost related to entity's assumptions of stock-based awards previously issued by acquired entities.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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-Publisher SEC
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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

+ References

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
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