Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2019	Feb. 14, 2020	Jun. 30, 2019
Cover page.
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	1-9533
Entity Registrant Name	WORLD FUEL SERVICES CORPORATION
Entity Incorporation, State or Country Code	FL
Entity Address, Address Line One	9800 N.W. 41st Street,
Entity Address, City or Town	Miami,
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	33178
Entity Tax Identification Number	59-2459427
City Area Code	305
Local Phone Number	428-8000
Title of 12(b) Security	Common Stock , $0.01 par value
Trading Symbol	INT
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 2,337,676,065
Entity Common Stock, Shares Outstanding		65,406,419
Entity Central Index Key	0000789460
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY