Reverse Stock Split (Details) shares in Millions	May. 20, 2015 shares
Reverse Stock Split [Abstract]
Common Stock, Shares Authorized Before Reverse Stock Split	900
Common Stock, Shares Authorized After Reverse Stock Split	225

The maximum number of common shares permitted to be issued by an entity's charter and bylaws before the effective date of a reverse stock split, without giving effect to the reverse stock split.

No definition available.

Name:	lxrx_CommonStockSharesAuthorizedBeforeReverseStockSplit
Namespace Prefix:	lxrx_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant