Document and Entity Information	3 Months Ended
	Mar. 31, 2014	Apr. 22, 2014
Document and Entity Information
Entity Registrant Name	Celldex Therapeutics, Inc.
Entity Central Index Key	0000744218
Document Type	10-Q
Document Period End Date	Mar. 31, 2014
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		89,357,843
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	Q1