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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Acquisitions (Narrative) (Details) $ in Millions				3 Months Ended	6 Months Ended
Acquisitions (Narrative) (Details) $ in Millions	Oct. 02, 2015 USD ($) country	Aug. 26, 2015 USD ($)	Jul. 02, 2015 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Business Acquisition
Cash paid for acquisitions, net of cash acquired					$ 3,284	$ 86
Fair Value, Inputs, Level 3 \| Minimum
Business Acquisition
Fair Value Inputs, Discount Rate					12.00%
Fair Value, Inputs, Level 3 \| Maximum
Business Acquisition
Fair Value Inputs, Discount Rate					14.00%
naviHealth
Business Acquisition
Cash paid for acquisitions, net of cash acquired		$ 238
Noncontrolling Interest, Ownership Percentage by Parent		71.00%
Cash Acquired from Acquisition		$ 53
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners		29.00%
Harvard Drug Group
Business Acquisition
Cash paid for acquisitions, net of cash acquired			$ 1,100
Cordis
Business Acquisition
Cash paid for acquisitions, net of cash acquired	$ 1,900
Number of countries in which the entity operates \| country	50
Transaction and integration costs				$ 20	$ 41
Customer relationships \| Minimum
Business Acquisition
Weighted-Average Useful Life					4 years
Customer relationships \| Maximum
Business Acquisition
Weighted-Average Useful Life					13 years
Trade Names [Member] \| Minimum
Business Acquisition
Weighted-Average Useful Life					10 years
Trade Names [Member] \| Maximum
Business Acquisition
Weighted-Average Useful Life					17 years
Developed technology and other \| naviHealth
Business Acquisition
Weighted-Average Useful Life					10 years