Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]
Antidilutive securities excluded from computation of earnings per share	8.2	7.9	5.7	5.1
Numerators for earnings per common share calculations:
Income from continuing operations	$ 1,260	$ 1,011	$ 3,338	$ 2,753
Net loss attributable to noncontrolling interest	0	0	0	2
Income from continuing operations attributable to CVS Caremark	1,260	1,011	3,338	2,755
Loss from discontinued operations, net of tax	(6)	(5)	(7)	(7)
Net income attributable to CVS Caremark	$ 1,254	$ 1,006	$ 3,331	$ 2,748
Denominators for earnings per common share calculations:
Weighted average common shares, basic (in shares)	1,218	1,265	1,226	1,281
Effect of dilutive securities:
Stock options (in shares)	7	8	7	8
Restricted stock units (in shares)	1	1	1	1
Weighted average common shares, diluted (in shares)	1,226	1,274	1,234	1,290
Basic earnings per common share:
Income from continuing operations attributable to CVS Caremark (usd per share)	$ 1.04	$ 0.80	$ 2.72	$ 2.15
Loss from discontinued operations attributable to CVS Caremark (usd per share)	$ (0.01)	$ 0.00	$ (0.01)	$ (0.01)
Diluted earnings per common share:
Income from continuing operations attributable to CVS Caremark (usd per share)	$ 1.03	$ 0.79	$ 2.70	$ 2.14
Loss from discontinued operations attributable to CVS Caremark (usd per share)	$ (0.01)	$ 0.00	$ (0.01)	$ (0.01)