Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2013	Mar. 04, 2014	Jun. 30, 2013
Document And Entity Information
Entity Registrant Name	ACME UNITED CORP
Entity Central Index Key	0000002098
Document Type	10-K
Document Period End Date	Dec. 31, 2013
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Is Entity a Well-known Seasoned Issuer?	No
Is Entity a Voluntary Filer?	No
Is Entity's Reporting Status Current?	Yes
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		3,201,102
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2013
Entity Public Float			$ 34,964,733