Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Earnings Per Share [Abstract]
Antidilutive securities excluded from computation of earnings per share	8.4	7.2	4.5	3.7
Numerators for earnings per common share calculations:
Income from continuing operations	$ 1,122	$ 966	$ 2,078	$ 1,742
Net loss attributable to noncontrolling interest	0	1	0	2
Income from continuing operations attributable to CVS Caremark	1,122	967	2,078	1,744
Loss from discontinued operations, net of tax	(1)	(1)	(1)	(2)
Net income attributable to CVS Caremark	$ 1,121	$ 966	$ 2,077	$ 1,742
Denominators for earnings per common share calculations:
Weighted average common shares, basic (in shares)	1,227	1,278	1,230	1,289
Effect of dilutive securities:
Stock options (in shares)	8	8	7	8
Restricted stock units (in shares)	1	1	1	1
Weighted average common shares, diluted (in shares)	1,236	1,287	1,238	1,298
Basic earnings per common share:
Income from continuing operations attributable to CVS Caremark (usd per share)	$ 0.91	$ 0.76	$ 1.69	$ 1.35
Loss from discontinued operations attributable to CVS Caremark (usd per share)	$ 0	$ 0	$ 0	$ 0
Net income attributable to CVS Caremark (usd per share)	$ 0.91	$ 0.76	$ 1.69	$ 1.35
Diluted earnings per common share:
Income from continuing operations attributable to CVS Caremark (usd per share)	$ 0.91	$ 0.75	$ 1.68	$ 1.34
Loss from discontinued operations attributable to CVS Caremark (usd per share)	$ 0	$ 0	$ 0	$ 0
Net income attributable to CVS Caremark (in dollars per share)	$ 0.91	$ 0.75	$ 1.68	$ 1.34