Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Jan. 31, 2020	Jun. 30, 2019
Cover page.
Local Phone Number	481-8100
Entity Address, City or Town	Cleveland
Entity Address, State or Province	OH
Entity Interactive Data Current	Yes
Entity Incorporation, State or Country Code	OH
Entity Tax Identification Number	34-1860551
Entity Address, Postal Zip Code	44117
City Area Code	216
Title of 12(b) Security	Common Shares, without par value
Entity Registrant Name	LINCOLN ELECTRIC HOLDINGS INC
Entity Central Index Key	0000059527
Document Type	10-K
Document Annual Report	true
Entity Address, Address Line One	22801 St. Clair Avenue
Document Period End Date	Dec. 31, 2019
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity File Number	0-1402
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 5,236,546,343
Entity Common Stock, Shares Outstanding		60,364,079
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Trading Symbol	LECO
Security Exchange Name	NASDAQ
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Document Transition Report	false