Goodwill, Other Intangibles, and Property and Equipment - Goodwill Activity (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 6,164	$ 5,980
Goodwill acquired, net	38,371	154
Impact of foreign currency translation	(30)	30
Goodwill, Ending Balance	44,505	$ 6,164
Integrated Medical [Member]
Goodwill [Line Items]
Goodwill, Ending Balance	10,500
Health Services [Member]
Goodwill [Line Items]
Goodwill, Ending Balance	33,700
International Markets [Member]
Goodwill [Line Items]
Goodwill, Ending Balance	$ 300

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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