Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Earnings Per Share
Common stock outstanding but not included in the calculation of diluted earnings per share (in shares)	7.2	34.6	3.7	29.2
Numerator for earnings per common share calculation:
Income from continuing operations	$ 966	$ 813	$ 1,742	$ 1,522
Net loss attributable to noncontrolling interest	1	1	2	2
Income from continuing operations attributable to CVS Caremark, basic (in dollars)	967	814	1,744	1,524
Loss From discontinued operations, net of tax	(1)	2	(2)	5
Net income attributable to CVS Caremark	$ 966	$ 816	$ 1,742	$ 1,529
Denominator for earnings per common share calculation:
Weighted average common shares, basic	1,278	1,355	1,289	1,359
Effect of dilutive securities:
Stock options (in shares)	8	7	8	8
Restricted stock units (in shares)	1	2	1	1
Weighted average common shares, diluted	1,287	1,364	1,298	1,368
Basic earnings per common share:
Income from continuing operations attributable to CVS Caremark (in dollars per share)	$ 0.76	$ 0.60	$ 1.35	$ 1.12
Net income attributable to CVS Caremark (in dollars per share)	$ 0.76	$ 0.60	$ 1.35	$ 1.13
Loss from discontinued operations attributable to CVS Caremark (in dollars per share)			$ 0
Diluted earnings per common share:
Income from continuing operations attributable to CVS Caremark (in dollars per share)	$ 0.75	$ 0.60	$ 1.34	$ 1.11
Net income attributable to CVS Caremark (in dollars per share)	$ 0.75	$ 0.60	$ 1.34	$ 1.12
Loss from discontinued operations attributable to CVS Caremark (in dollars per share)			$ 0