Document and Entity Information Document	9 Months Ended
	Sep. 30, 2014	Nov. 04, 2014
Document Information [Line Items]
Entity Registrant Name	LEXICON PHARMACEUTICALS, INC./DE
Entity Central Index Key	0001062822
Document Type	10-Q
Document Period End Date	Sep. 30, 2014
Amendment Flag	false
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		514,834,527