Significant Accounting Policies - Impact of New Lease Standard On Balance Sheet Line Items (Details) - USD ($) $ in Millions	Jun. 30, 2019	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other current assets	$ 4,691		$ 4,533	$ 4,581
Total current assets	46,901		45,195	45,243
Property and equipment, net	11,483		11,360	11,349
Operating lease right-of-use assets	20,865		20,987	0
Intangible assets, net	34,163		36,307	36,524
Other assets	4,763		4,525	5,046
Total assets	218,904		216,668	196,456
Accrued expenses	10,562		10,659	10,711
Current portion of operating lease liabilities	1,793		1,803	0
Current portion of long-term debt	3,894		1,267	1,265
Total current liabilities	49,376		45,762	44,009
Long-term operating lease liabilities	18,849		18,832	0
Long-term debt	66,941		71,348	71,444
Deferred income taxes	7,375		7,740	7,677
Other long-term liabilities	2,528		2,262	2,780
Total liabilities	157,305		157,947	137,913
Retained earnings	43,136		41,089	40,911
Total CVS Health shareholders’ equity	61,282		58,403	58,225
Total shareholders’ equity	$ 61,599	$ 60,006	58,721	$ 58,543	$ 35,611	$ 38,677	$ 37,695
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other current assets			(48)
Total current assets			(48)
Property and equipment, net			11
Operating lease right-of-use assets			20,987
Intangible assets, net			(217)
Other assets			(521)
Total assets			20,212
Accrued expenses			(52)
Current portion of operating lease liabilities			1,803
Current portion of long-term debt			2
Total current liabilities			1,753
Long-term operating lease liabilities			18,832
Long-term debt			(96)
Deferred income taxes			63
Other long-term liabilities			(518)
Total liabilities			20,034
Retained earnings			178
Total CVS Health shareholders’ equity			178
Total shareholders’ equity			$ 178