Document And Entity Information	12 Months Ended
	Dec. 31, 2017 shares
Document and Entity Information [Abstract]
Entity Registrant Name	FRONTLINE LTD /
Entity Central Index Key	0000913290
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding	169,809,324
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	FY
Document Type	20-F
Amendment Flag	false
Document Period End Date	Dec. 31, 2017