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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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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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The net carrying amount as of the balance sheet date of other indefinite-lived and finite-lived intangible assets that are not separately presented on the statement of financial position.

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No definition available.

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Goodwill, Customer Relationships and Other Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2013	Jan. 03, 2013
Intangible assets
Impairment of goodwill	$ 1,100us-gaap_GoodwillImpairmentLoss	$ 0us-gaap_GoodwillImpairmentLoss	$ 1,092us-gaap_GoodwillImpairmentLoss	$ 0us-gaap_GoodwillImpairmentLoss
Goodwill		20,755us-gaap_Goodwill	20,674us-gaap_Goodwill		21,627us-gaap_Goodwill	21,627us-gaap_Goodwill
Indefinite-life intangible assets		268	321
Other intangible assets, net		1,647us-gaap_OtherIntangibleAssetsNet	1,802us-gaap_OtherIntangibleAssetsNet
Amortization of intangible assets		1,470us-gaap_AmortizationOfIntangibleAssets	1,589us-gaap_AmortizationOfIntangibleAssets	1,710us-gaap_AmortizationOfIntangibleAssets
Customer relationships
Intangible assets
Finite lived intangible assets, net		4,893	5,935
Accumulated amortization		4,683	3,641
Capitalized software
Intangible assets
Finite lived intangible assets, net		1,338	1,415
Accumulated amortization		1,533	1,193
Tradenames and patents
Intangible assets
Finite lived intangible assets, net		41	66
Accumulated amortization		$ 196	$ 208