Benefit Plan	12 Months Ended
Dec. 31, 2014
Benefit Plan [Abstract]
Benefit Plan	Benefit Plan Lexicon maintains a defined-contribution savings plan under Section 401(k) of the Internal Revenue Code. The plan covers substantially all full-time employees. Participating employees may defer a portion of their pretax earnings, up to the Internal Revenue Service annual contribution limit. Beginning in 2000, the Company was required to match employee contributions according to a specified formula. The matching contributions totaled $376,000, $511,000 and $490,000 in the years ended December 31, 2014, 2013 and 2012, respectively. Company contributions are vested based on the employee’s years of service, with full vesting after four years of service.

Benefit Plan

12 Months Ended

Dec. 31, 2014

Lexicon maintains a defined-contribution savings plan under Section 401(k) of the Internal Revenue Code. The plan covers substantially all full-time employees. Participating employees may defer a portion of their pretax earnings, up to the Internal Revenue Service annual contribution limit. Beginning in 2000, the Company was required to match employee contributions according to a specified formula. The matching contributions totaled $376,000, $511,000 and $490,000 in the years ended December 31, 2014, 2013 and 2012, respectively. Company contributions are vested based on the employee’s years of service, with full vesting after four years of service.