Segment Reporting (Details) (USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013 type_of_transaction segment		Sep. 30, 2012	Dec. 31, 2012
Segment reporting information
Number of segments					3
Net revenues	$ 31,968,000,000		$ 30,227,000,000		$ 93,979,000,000		$ 91,739,000,000
Gross profit	6,035,000,000		5,647,000,000		17,452,000,000		16,209,000,000
Operating profit (loss)(3)	2,161,000,000		1,814,000,000		5,828,000,000		4,925,000,000
Total assets	67,805,000,000				67,805,000,000			65,912,000,000
Goodwill	26,550,000,000				26,550,000,000			26,395,000,000
Number of type of transactions related to intersegment eliminations					2
Intersegment eliminations, intersegment revenues	1,100,000,000		841,000,000		3,100,000,000		2,500,000,000
Gain on antitrust legal settlement with a prescription drug manufacturer	72,000,000
Pharmacy Services Segment
Segment reporting information
Number of states pharmacies operated	22				22
Net revenues	19,483,000,000	[1]	18,079,000,000	[1]	56,593,000,000		54,802,000,000
Gross profit	1,294,000,000	[1]	1,081,000,000	[1]	3,025,000,000		2,474,000,000
Operating profit (loss)(3)	1,012,000,000	[1]	784,000,000	[1]	2,186,000,000		1,644,000,000
Total assets	37,274,000,000	[1]			37,274,000,000	[1]		36,057,000,000	[1]
Goodwill	19,657,000,000	[1]			19,657,000,000	[1]		19,646,000,000	[1]
Net revenues, retail co-payments	1,900,000,000		2,000,000,000		6,100,000,000		6,400,000,000
Gain on antitrust legal settlement with a prescription drug manufacturer	11,000,000
Pharmacy Services Segment | Specialty stores
Segment reporting information
Number of pharmacies	30				30
Pharmacy Services Segment | Specialty mail order
Segment reporting information
Number of pharmacies	12				12
Pharmacy Services Segment | Mail service
Segment reporting information
Number of pharmacies	4				4
Retail Pharmacy Segment
Segment reporting information
Number of states pharmacies operated	42				42
Number of retail drugstores	7,601				7,601
Net revenues	16,284,000,000		15,504,000,000		48,474,000,000		47,373,000,000
Gross profit	4,884,000,000		4,672,000,000		14,836,000,000		14,014,000,000
Operating profit (loss)(3)	1,471,000,000		1,305,000,000		4,604,000,000		4,071,000,000
Total assets	30,048,000,000				30,048,000,000			29,183,000,000
Goodwill	6,893,000,000				6,893,000,000			6,749,000,000
Intersegment eliminations, intersegment gross profit	143,000,000		106,000,000		409,000,000		279,000,000
Gain on antitrust legal settlement with a prescription drug manufacturer	61,000,000
Number of retail drugstores operating a pharmacy	7,541				7,541
Retail Pharmacy Segment | MinuteClinic within CVS Pharmacy Stores
Segment reporting information
Number of clinics in retail drugstores	718				718
Retail Pharmacy Segment | MinuteClinic
Segment reporting information
Number of clinics	726				726
Retail Pharmacy Segment | Specialty stores
Segment reporting information
Number of pharmacies	18				18
Corporate Segment
Segment reporting information
Net revenues	0		0		0		0
Gross profit	0		0		0		0
Operating profit (loss)(3)	(179,000,000)		(169,000,000)		(553,000,000)		(511,000,000)
Total assets	1,679,000,000				1,679,000,000			1,408,000,000
Goodwill	0				0			0
Intersegment Eliminations
Segment reporting information
Net revenues	(3,799,000,000)	[2]	(3,356,000,000)	[2]	(11,088,000,000)		(10,436,000,000)
Gross profit	(143,000,000)	[2]	(106,000,000)	[2]	(409,000,000)		(279,000,000)
Operating profit (loss)(3)	(143,000,000)	[2]	(106,000,000)	[2]	(409,000,000)		(279,000,000)
Total assets	(1,196,000,000)	[2]			(1,196,000,000)	[2]		(736,000,000)	[2]
Goodwill	$ 0	[2]			$ 0	[2]		$ 0	[2]

[1] Net revenues of the Pharmacy Services Segment include approximately $1.9 billion and $2.0 billion of retail co-payments for the three months ended September 30, 2013 and 2012, respectively

[2] Intersegment eliminations relate to two types of transactions: (i) Intersegment revenues that occur when Pharmacy Services Segment customers use Retail Pharmacy Segment stores to purchase covered products. When this occurs, both the Pharmacy Services and Retail Pharmacy segments record the revenue on a standalone basis, and (ii) Intersegment revenues, gross profit and operating profit that occur when Pharmacy Services Segment customers, through the Company’s intersegment activities (such as the Maintenance Choice® program), elect to pick-up their maintenance prescriptions at Retail Pharmacy Segment stores instead of receiving them through the mail. When this occurs, both the Pharmacy Services and Retail Pharmacy segments record the revenue, gross profit and operating profit on a standalone basis. The following amounts are eliminated in consolidation in connection with the item (ii) intersegment activity: net revenues of $1.1 billion and $841 million for the three months ended September 30, 2013 and 2012, respectively, and $3.1 billion and $2.5 billion for the nine months ended September 30, 2013 and 2012 respectively; gross profit and operating profit of $143 million and $106 million for the three months ended September 30, 2013 and 2012, respectively, and $409 million and $279 million for the nine months ended September 30, 2013 and 2012, respectively.