Subsequent Events (Details) In Millions, unless otherwise specified	Oct. 21, 2014 USD ($)	Oct. 21, 2014 EUR (€)
Subsequent Event [Line Items]
Ipsen Upfront Payment	$ 23
Ipsen Regulatory And Commercial Launch Milestones	30
Ipsen Sales Milestones		€ 72

On October 21, 2014, Lexicon entered into a License and Collaboration Agreement with Ipsen Pharma SAS for the development of Lexicon's drug candidate LX1032 (telotristat etiprate) outside the United States, Canada and Japan. This represents the potential regulatory and commercial launch milestone payments under the agreement.

No definition available.

Name:	lxrx_IpsenRegulatoryAndCommercialLaunchMilestones
Namespace Prefix:	lxrx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant