Consolidated Statements of Operations Parentheticals (Unaudited) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Stock-based compensation expense associated with research and development expense	$ 818	$ 809	$ 1,657	$ 1,615
Stock-based compensation expense associated with general and administrative expense	$ 632	$ 511	$ 1,265	$ 1,010

Name:

lxrx_StockBasedCompensationExpenseAssociatedWithGeneralAndAdministrativeExpense

Namespace Prefix:

lxrx

Data Type:

xbrli:monetaryItemType

Balance Type:

debit

Period Type:

duration