Intangible Assets and Goodwill (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2012 Y	Mar. 31, 2011	Dec. 31, 2011 Y
Intangible assets
Weighted Amortizable Life (in years)	13		13
Gross Carrying Amount	$ 4,921		$ 4,904
Accumulated Amortization	(652)		(554)
Net	4,269		4,350
Indefinite-lived intangible assets in process research & development	18		18
Total intangible assets, net	4,287		4,368
Total intangible assets, gross carrying amount	4,939		4,922
Finite-lived intangible assets acquired	8
Amortization expense	94	22
2012	375
2013	372
2014	367
2015	362
2016	352
Thereafter	2,553
Customer relationships
Intangible assets
Weighted Amortizable Life (in years)	15		15
Gross Carrying Amount	2,811		2,811
Accumulated Amortization	(262)		(213)
Net	2,549		2,598
Intellectual property
Intangible assets
Weighted Amortizable Life (in years)	11		11
Gross Carrying Amount	1,805		1,794
Accumulated Amortization	(283)		(244)
Net	1,522		1,550
Other
Intangible assets
Weighted Amortizable Life (in years)	10		11
Gross Carrying Amount	305		299
Accumulated Amortization	(107)		(97)
Net	$ 198		$ 202

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The total gross carrying amount of finite-lived and indefinite-lived intangible assets, excluding goodwill.

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The aggregate amount assigned to a major class of finite-lived intangible assets acquired either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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The aggregate cost of a major indefinite-lived intangible asset class acquired, during the period, either individually or as part of a group of assets (in either an asset acquisition or business combination).

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The accumulated amount of amortization of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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Sum of the gross carrying amounts before accumulated amortization as of the balance sheet date of all intangible assets having statutory or estimated useful lives. The aggregate gross carrying amount (including any previously recognized impairment charges) of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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The aggregate sum of gross carrying value of a major finite-lived intangible asset class, less accumulated amortization and any impairment charges. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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The calculated weighted-average useful life of all finite-lived intangible assets.

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The amount of amortization expense expected to be recognized for the remainder of the finite-lived intangible asset useful life after the fifth succeeding fiscal year.

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No definition available.

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The amount of amortization expense expected to be recognized during year five of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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