Summary of Significant Accounting Policies Concentration of Credit Risk (Policies)

12 Months Ended

Dec. 31, 2012

Concentration of Credit Risk [Abstract]

Concentration Risk Disclosure [Text Block]

Concentration of Credit Risk: Lexicon's cash equivalents, investments and accounts receivable represent potential concentrations of credit risk. The Company attempts to minimize potential concentrations of risk in cash equivalents and investments by placing investments in high-quality financial instruments. The Company’s accounts receivable are unsecured and are concentrated in pharmaceutical and biotechnology companies located in the United States and Europe.  The Company has not experienced any significant credit losses to date.