Document and Entity Information Document (USD $)	12 Months Ended
	Dec. 31, 2014	Feb. 13, 2015	Jun. 30, 2014
Document And Entity Information [Abstract]
Entity Registrant Name	Gilead Sciences Inc
Entity Central Index Key	0000882095
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2014
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Amendment Flag	false
Entity Common Stock, Shares Outstanding		1,489,401,683
Entity Current Reporting Status	No
Entity Public Float			$ 99,821,731,329