Consolidated Statements of Shareholders' Equity - USD ($) shares in Millions, $ in Millions		Total	Common Shares	Treasury Shares		Common Stock and Capital Surplus	[2]	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Total CVS Health Shareholders' Equity	Noncontrolling Interest
Balance at beginning of period (in shares) at Dec. 31, 2016			1,705	(644)	[1]
Beginning of year balance at Dec. 31, 2016		$ 36,834		$ (33,483)	[1]	$ 31,635		$ 38,983	$ (305)	$ 36,830	$ 4
Stockholders' Equity [Roll Forward]
Net income (loss)		6,623						6,622		6,622	1
Other comprehensive income (Note 13)		140							140	140
Stock option activity, stock awards and other (in shares)			7
Stock option activity, stock awards and other		461				461				461
Purchase of treasury shares, net of ESPP issuances (in shares)	[1]			(54)
Purchase of treasury shares, net of ESPP issuances		(4,313)		$ (4,313)	[1]					(4,313)
Common stock dividends		(2,049)						(2,049)		(2,049)
Other decreases in noncontrolling interests		(1)									(1)
Balance at end of period (in shares) at Dec. 31, 2017			1,712	(698)	[1]
End of year balance at Dec. 31, 2017		37,695		$ (37,796)	[1]	32,096		43,556	(165)	37,691	4
Stockholders' Equity [Roll Forward]
Net income (loss)		(596)						(594)		(594)	(2)
Other comprehensive income (Note 13)		274							274	274
Common shares issued to acquire Aetna (in shares)	[1]			274
Common shares issued to acquire Aetna		22,484		$ 9,561	[1]	12,923				22,484
Stock option activity, stock awards and other (in shares)			8
Stock option activity, stock awards and other		421				421				421
Purchase of treasury shares, net of ESPP issuances (in shares)	[1]			(1)
Purchase of treasury shares, net of ESPP issuances		7		$ 7	[1]					7
Common stock dividends		(2,045)						(2,045)		(2,045)
Acquisition of noncontrolling interests		329									329
Other decreases in noncontrolling interests		(13)									(13)
Balance at end of period (in shares) at Dec. 31, 2018			1,720	(425)	[1]
End of year balance at Dec. 31, 2018		58,543		$ (28,228)	[1]	45,440		40,911	102	58,225	318
Stockholders' Equity [Roll Forward]
Net income (loss)		6,631						6,634		6,634	(3)
Other comprehensive income (Note 13)		917							917	917
Stock option activity, stock awards and other (in shares)			7	2
Stock option activity, stock awards and other		532				532				532
Purchase of treasury shares, net of ESPP issuances (in shares)	[1]			(2)
Purchase of treasury shares, net of ESPP issuances		(7)		$ (7)	[1]					(7)
Common stock dividends		(2,615)						(2,615)		(2,615)
Other decreases in noncontrolling interests		(9)									(9)
Balance at end of period (in shares) at Dec. 31, 2019			1,727	(425)	[1]
End of year balance at Dec. 31, 2019		$ 64,170		$ (28,235)	[1]	$ 45,972		$ 45,108	$ 1,019	$ 63,864	$ 306

[1] Treasury shares include 1 million shares held in trust for each of the years ended December 31, 2019, 2018 and 2017. Treasury stock includes $29 million related to shares held in trust for each of the years ended December 31, 2019 and 2018 and $31 million related to shares held in trust for the year ended December 31, 2017. See Note 1 ‘‘Significant Accounting Policies’’ for additional information.

[2] Common stock and capital surplus includes the par value of common stock of $17 million as of December 31, 2019, 2018 and 2017.