Accounting Policies - Impact of New Revenue Recognition Standard on Financial Statement Line Items (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jan. 01, 2018	Dec. 31, 2017
Condensed Consolidated Statements of Operations
Net revenue	$ 47,269		$ 139,670
Cost of revenue	39,941	$ 39,064	118,282	$ 115,766
Gross profit	7,328	7,117	21,388	20,614
Operating profit	2,353	2,499	2,712	6,409
Income before income tax provision	1,899	2,062	1,304	5,459
Income tax provision	509	777	1,478	2,115
Income (loss) from continuing operations	1,390	1,285	(174)	3,344
Net income (loss)	1,390	1,285	(175)	3,336
Net income (loss) attributable to CVS Health	1,390	1,285	(175)	3,335
Condensed Consolidated Balance Sheets
Accrued expenses	6,160		6,160		$ 6,626	$ 6,609
Deferred income taxes	3,052		3,052		2,992	2,996
Total Liabilities	94,884		94,884		57,449	57,436
Retained earnings	41,843		41,843		43,543	43,556
Total CVS Health shareholders’ equity	36,618		36,618		37,678	37,691
Total shareholders’ equity	36,622		36,622		37,682	$ 37,695
Reconciliation of net loss to net cash provided by operating activities:
Net income (loss)	1,390	$ 1,285	(175)	3,336
Deferred income taxes and other noncash items			296	271
Accrued expenses			(341)	$ 1,670
ASU 2014-09 | Adjustment
Condensed Consolidated Statements of Operations
Net revenue	6		(4)
Cost of revenue	3		(3)
Gross profit	3		(1)
Operating profit	3		(1)
Income before income tax provision	3		(1)
Income tax provision	1
Income (loss) from continuing operations	2		(1)
Net income (loss)	2		(1)
Net income (loss) attributable to CVS Health	2		(1)
Condensed Consolidated Balance Sheets
Accrued expenses	18		18		17
Deferred income taxes	(4)		(4)		(4)
Total Liabilities	14		14		13
Retained earnings	(14)		(14)		(13)
Total CVS Health shareholders’ equity	(14)		(14)		(13)
Total shareholders’ equity	(14)		(14)		$ (13)
Reconciliation of net loss to net cash provided by operating activities:
Net income (loss)	2		(1)
Accrued expenses			1
ASU 2014-09 | As previously reported
Condensed Consolidated Statements of Operations
Net revenue	47,263		139,674
Cost of revenue	39,938		118,285
Gross profit	7,325		21,389
Operating profit	2,350		2,713
Income before income tax provision	1,896		1,305
Income tax provision	508		1,478
Income (loss) from continuing operations	1,388		(173)
Net income (loss)	1,388		(174)
Net income (loss) attributable to CVS Health	1,388		(174)
Condensed Consolidated Balance Sheets
Accrued expenses	6,142		6,142
Deferred income taxes	3,056		3,056
Total Liabilities	94,870		94,870
Retained earnings	41,857		41,857
Total CVS Health shareholders’ equity	36,632		36,632
Total shareholders’ equity	36,636		36,636
Reconciliation of net loss to net cash provided by operating activities:
Net income (loss)	$ 1,388		(174)
Accrued expenses			$ (342)