Subsequent Events	9 Months Ended
Sep. 30, 2014
Subsequent Event [Line Items]
Subsequent Events	Subsequent Events On October 21, 2014, Lexicon entered into a License and Collaboration Agreement (the “Agreement”) with Ipsen Pharma SAS (“Ipsen”) for the development and commercialization of Lexicon’s drug candidate LX1032 (telotristat etiprate) outside of the United States, Canada and Japan (the “Licensed Territory”). Under the Agreement, the Company granted Ipsen an exclusive, royalty-bearing right and license under its patent rights and know-how to commercialize LX1032 in the Licensed Territory. Ipsen is responsible for using diligent efforts to commercialize LX1032 in the Licensed Territory pursuant to a mutually approved commercialization plan. Subject to certain exceptions, the Company will be responsible for conducting clinical trials required to obtain regulatory approval for LX1032 for carcinoid syndrome in the European Union, including those contemplated by a mutually approved initial development plan, and will have the first right to conduct most other clinical trials of LX1032. The Company is responsible for the costs of all clinical trials contemplated by the initial development plan. The costs of additional clinical trials will be allocated between the parties based on the nature of such clinical trials. Under the Agreement, Ipsen will pay the Company an upfront payment of $23 million. In addition, the Company is eligible to receive from Ipsen (a) up to an aggregate of approximately $30 million upon the achievement of specified regulatory and commercial launch milestones and (b) up to an aggregate of €72 million upon the achievement of specified sales milestones. The Company is also entitled to tiered, escalating royalties ranging from low twenties to mid-thirties percentages of net sales of LX1032 in the Licensed Territory, subject to a credit for amounts previously paid to Lexicon by Ipsen for the manufacture and supply of such units of LX1032. The Company’s receipt of these payments under the Agreement will trigger its obligation to make certain contingent payments to Holdings pursuant to the Company’s prior arrangement with Holdings for the financing of the clinical development of LX1032 (see Note 9, Arrangements with Symphony Icon, Inc., for more information). Lexicon and Ipsen will enter into a commercial supply agreement pursuant to which the Company will supply Ipsen’s commercial requirements of LX1032, and Ipsen will pay an agreed upon transfer price for such commercial supply.

Subsequent Events

On October 21, 2014, Lexicon entered into a License and Collaboration Agreement (the “Agreement”) with Ipsen Pharma SAS (“Ipsen”) for the development and commercialization of Lexicon’s drug candidate LX1032 (telotristat etiprate) outside of the United States, Canada and Japan (the “Licensed Territory”).

Under the Agreement, the Company granted Ipsen an exclusive, royalty-bearing right and license under its patent rights and know-how to commercialize LX1032 in the Licensed Territory. Ipsen is responsible for using diligent efforts to commercialize LX1032 in the Licensed Territory pursuant to a mutually approved commercialization plan.

Subject to certain exceptions, the Company will be responsible for conducting clinical trials required to obtain regulatory approval for LX1032 for carcinoid syndrome in the European Union, including those contemplated by a mutually approved initial development plan, and will have the first right to conduct most other clinical trials of LX1032. The Company is responsible for the costs of all clinical trials contemplated by the initial development plan. The costs of additional clinical trials will be allocated between the parties based on the nature of such clinical trials.

Under the Agreement, Ipsen will pay the Company an upfront payment of $23 million. In addition, the Company is eligible to receive from Ipsen (a) up to an aggregate of approximately $30 million upon the achievement of specified regulatory and commercial launch milestones and (b) up to an aggregate of €72 million upon the achievement of specified sales milestones. The Company is also entitled to tiered, escalating royalties ranging from low twenties to mid-thirties percentages of net sales of LX1032 in the Licensed Territory, subject to a credit for amounts previously paid to Lexicon by Ipsen for the manufacture and supply of such units of LX1032. The Company’s receipt of these payments under the Agreement will trigger its obligation to make certain contingent payments to Holdings pursuant to the Company’s prior arrangement with Holdings for the financing of the clinical development of LX1032 (see Note 9, Arrangements with Symphony Icon, Inc., for more information).

Lexicon and Ipsen will enter into a commercial supply agreement pursuant to which the Company will supply Ipsen’s commercial requirements of LX1032, and Ipsen will pay an agreed upon transfer price for such commercial supply.