Represents the term of line of credit facility.

No definition available.

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- Definition

The amount of fees paid for extension of bridge loan facility.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

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-Publisher FASB
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-SubTopic 30
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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-Publisher FASB
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (e)
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_BusinessAcquisitionAxis=cvs_AetnaAcquisitionMember
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Balance Type:
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- Details

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- Details

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Borrowings and Credit Agreements - Additional Information (Details) - USD ($)			3 Months Ended
	Mar. 09, 2018	Dec. 03, 2017	Mar. 31, 2018	Dec. 31, 2017	Dec. 15, 2017
Borrowings and Credit Agreements
Carrying amount of long-term debt			$ 65,100,000,000
Aetna Acquisition
Borrowings and Credit Agreements
Redemption percentage			101.00%
Unsecured senior notes of $40 billion
Borrowings and Credit Agreements
Debt instrument, face amount	$ 40,000,000,000
Proceeds from issuance of debt	39,400,000,000
Carrying amount of long-term debt	40,000,000,000
3.125% senior notes due 2020
Borrowings and Credit Agreements
Debt instrument, face amount	$ 2,000,000,000
Interest rate, stated percentage	3.125%
Floating rate notes due 2020
Borrowings and Credit Agreements
Debt instrument, face amount	$ 1,000,000,000
3.35% senior notes due 2021
Borrowings and Credit Agreements
Debt instrument, face amount	$ 3,000,000,000
Interest rate, stated percentage	3.35%
Floating rate notes due 2021
Borrowings and Credit Agreements
Debt instrument, face amount	$ 1,000,000,000
3.7% senior notes due 2023
Borrowings and Credit Agreements
Debt instrument, face amount	$ 6,000,000,000
Interest rate, stated percentage	3.70%
4.1% senior notes due 2025
Borrowings and Credit Agreements
Debt instrument, face amount	$ 5,000,000,000
Interest rate, stated percentage	4.10%
4.3% senior notes due 2028
Borrowings and Credit Agreements
Debt instrument, face amount	$ 9,000,000,000
Interest rate, stated percentage	4.30%
4.78% senior notes due 2038
Borrowings and Credit Agreements
Debt instrument, face amount	$ 5,000,000,000
Interest rate, stated percentage	4.78%
5.05% senior notes due 2048
Borrowings and Credit Agreements
Debt instrument, face amount	$ 8,000,000,000
Interest rate, stated percentage	5.05%
Term loan in connection with Aetna purchase \| Aetna Acquisition
Borrowings and Credit Agreements
Debt instrument, face amount					$ 5,000,000,000
Unsecured Backup Credit Facilities
Borrowings and Credit Agreements
Commitment fee percentage			0.02%
Long-term line of credit			$ 0	$ 0
Unsecured Backup Credit Facilities \| Unsecured Backup Credit Facility Expiring May 17, 2018
Borrowings and Credit Agreements
Maximum borrowing capacity			$ 1,000,000,000
Line of credit facility term (in years)			364 days
Unsecured Backup Credit Facilities \| Unsecured Backup Credit Facility Expiring July 24, 2019
Borrowings and Credit Agreements
Maximum borrowing capacity			$ 1,250,000,000
Line of credit facility term (in years)			5 years
Unsecured Backup Credit Facilities \| Unsecured Backup Credit Facility Expiring July 1, 2020
Borrowings and Credit Agreements
Maximum borrowing capacity			$ 1,250,000,000
Line of credit facility term (in years)			5 years
Unsecured Backup Credit Facilities \| Unsecured Backup Credit Facility Expiring May 18, 2022
Borrowings and Credit Agreements
Maximum borrowing capacity			$ 1,000,000,000
Line of credit facility term (in years)			5 years
Unsecured Debt \| Unsecured Bridge Loan \| Aetna Acquisition
Borrowings and Credit Agreements
Debt issuance fees paid		$ 221,000,000
Amortization of loan facility fees			$ 161,000,000
Debt instrument, face amount		$ 49,000,000,000			$ 44,000,000,000
Carrying amount of long-term debt	$ 4,000,000,000
Extension fees paid for extension of bridge loan facility	$ 8,000,000