Segment Reporting (Details) $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($) state segment pharmacy item store Center	Mar. 31, 2016 USD ($)
Segment reporting information
Number of reportable segments \| segment	3
Net revenues	$ 44,514	$ 43,215
Gross profit	6,580	6,744
Operating profit (loss)	1,793	2,185
Restructuring charge incurred	$ 199
ASU 2017-17
Segment reporting information
Operating profit (loss)		9
Pharmacy Services Segment
Segment reporting information
Centers of excellence for infusion and enteral services \| Center	3
Number of states pharmacies operated \| state	41
Net revenues	$ 31,223	28,765
Gross profit	1,096	1,102
Operating profit (loss)	784	784
Net revenues, retail co-payments	$ 3,100	3,000
Retail/LTC Segment
Segment reporting information
Number of states pharmacies operated \| state	49
Number of retail drugstores \| item	9,676
Number of retail drugstores operating a pharmacy \| item	7,948
Number of LTC spoke pharmacies \| item	151
Number of LTC hub pharmacies \| item	32
Net revenues	$ 19,341	20,112
Gross profit	5,676	5,830
Operating profit (loss)	1,411	1,784
Restructuring charge incurred	199
Integration related costs	15
Retail/LTC Segment \| Gross Profit
Segment reporting information
Integration related costs		4
Retail/LTC Segment \| Operating profit
Segment reporting information
Integration related costs		61
Corporate Segment
Segment reporting information
Operating profit (loss)	(226)	(212)
Intersegment Eliminations
Segment reporting information
Net revenues	(6,050)	(5,662)
Gross profit	(192)	(188)
Operating profit (loss)	$ (176)	$ (171)
Minute Clinic Within C V S Pharmacy Stores \| Retail/LTC Segment
Segment reporting information
Number of clinics in retail drugstores \| item	1,118
CarePlus and CVS Pharmacy \| Retail/LTC Segment
Segment reporting information
Number of pharmacies (more than 68,000) \| pharmacy	40
MinuteClinic \| Retail/LTC Segment
Segment reporting information
Number of clinics \| item	1,125
Target Pharmacy Acquisition \| Retail/LTC Segment
Segment reporting information
Number of retail drugstores operating a pharmacy \| store	1,678
Specialty stores \| Pharmacy Services Segment
Segment reporting information
Number of pharmacies (more than 68,000) \| pharmacy	23
Specialty mail order \| Pharmacy Services Segment
Segment reporting information
Number of pharmacies (more than 68,000) \| pharmacy	13
Mail service \| Pharmacy Services Segment
Segment reporting information
Number of pharmacies (more than 68,000) \| pharmacy	4
Infusion and Enteral Branches \| Pharmacy Services Segment
Segment reporting information
Number of infusion and enteral branches \| pharmacy	84
Ambulatory Infusion Suites \| Pharmacy Services Segment
Segment reporting information
Number of infusion and enteral branches \| pharmacy	73

Centers of Excellence for Infusion and Enteral Services

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