Line items represent reporting 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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 12
-Sentence Column A

+ Details

Name:	invest_InvestmentLineItems
Namespace Prefix:	invest_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Gain (Loss) From Contribution Agreement

+ References

No definition available.

+ Details

Name:	pfe_GainLossFromContributionAgreement
Namespace Prefix:	pfe_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Investment, Ownership Percentage

+ References

No definition available.

+ Details

Name:	pfe_InvestmentOwnershipPercentage
Namespace Prefix:	pfe_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Payments To Collaborators

+ References

No definition available.

+ Details

Name:	pfe_PaymentsToCollaborators
Namespace Prefix:	pfe_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

+ Details

Name:	us-gaap_EquitySecuritiesFvNi
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

Name:	us-gaap_SharePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=pfe_AllogeneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=pfe_CellectisMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=pfe_LongtermInvestmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=pfe_AllogeneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Acquisition, Divestitures, Licensing Arrangements, Collaborative Arrangements and Privately Held Investment - Allogene (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		3 Months Ended	9 Months Ended	12 Months Ended
	Oct. 31, 2018	Apr. 30, 2018	Jul. 01, 2018	Sep. 30, 2018	Dec. 31, 2014	Dec. 31, 2017
Investment [Line Items]
Fair value of equity investment				$ 1,213		$ 2,150
Allogene [Member]
Investment [Line Items]
Investment ownership percentage		25.00%
Non-cash pre-tax gain from the difference between the fair value of equity investment received and book value of assets transferred			$ 50	50
Cellectis [Member]
Investment [Line Items]
Investment ownership percentage					7.00%
Upfront payment to Cellectis					$ 80
Subsequent Event [Member] \| Allogene [Member]
Investment [Line Items]
Investment ownership percentage	19.00%
Long-term Investments [Member] \| Allogene [Member]
Investment [Line Items]
Fair value of equity investment				$ 127
Allogene [Member] \| Subsequent Event [Member]
Investment [Line Items]
Price per share (in dollars per share)	$ 25