Acquisitions (Allocation Of Acquisition Costs) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Business Acquisition [Line Items]
Intangible asset useful life	10 years
Cash	$ 575	$ 139
Estimated fair value of deferred/contingent consideration	197	39	46
Total consideration	772	178
Allocation of purchase price:
Goodwill	7,241us-gaap_Goodwill	6,893us-gaap_Goodwill	6,792us-gaap_Goodwill
Current Fiscal Period Acquisitions [Member]
Business Acquisition [Line Items]
Cash	575
Estimated fair value of deferred/contingent consideration	197
Total consideration	772
Allocation of purchase price:
Cash and cash equivalents	21
Accounts receivable, net	12
Other current assets	1
Property, plant, and equipment	5
Intangible assets (primarily customer lists amortized over 10 years)	318
Goodwill	472
Other assets	7
Total assets acquired	836
Current liabilities	41
Other liabilities	23
Total liabilities assumed	64
Net assets acquired	$ 772

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Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Including Goodwill

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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