Acquisition of Aetna - Pro Forma (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Business Combinations [Abstract]
Total revenues	$ 243,232	$ 236,000
Income from continuing operations	$ 1,152	$ 6,813
Basic earnings per share from continuing operations attributable to CVS Health (in dollars per share)	$ 0.89	$ 5.25
Diluted earnings (loss) per share from continuing operations attributable to CVS Health (in dollars per share)	$ 0.88	$ 5.21

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
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-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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