Subsequent Event	9 Months Ended
Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventOn November 9, 2021, we announced we are pursuing plans to split Ligand into two separate, publicly traded companies with one featuring the OmniAb platform and its large and growing customer base, and the other featuring Ligand’s existing collection of core royalties and the technologies, pipeline and contracts associated with the Pelican protein expression platform and the Captisol business. Based on initial management and advisor review, an IPO and eventual distribution of OmniAb shares to Ligand shareholders is the leading option under consideration at this time. The IPO would be of newly issued shares of OmniAb, Inc. (formerly OMT), including Ab Initio computational antigen design, Icagen’s ion channel technology, xPloration high-throughput screening technology, and the suite of OmniAb animals used for antibody discovery. In an IPO, we expect OmniAb to issue less than 20% of its common stock, with us retaining the remaining interest, which would eventually be distributed to our stockholders in a manner generally intended to qualify as a tax-free transaction. Our Board of Directors has not approved a specific course of action, and we will continue to evaluate other options to optimize value and ensure flexibility to invest in growth. There can be no assurance that this process will result in us pursuing a particular transaction or consummating any such transaction. We do not expect to disclose further developments relating to this strategic review process, unless and until our Board of Directors approves a specific transaction or otherwise concludes this review. There can be no assurance that this process will result in the Company pursuing a particular transaction or consummating any such transaction.

Subsequent Event

9 Months Ended

Sep. 30, 2021

Subsequent EventOn November 9, 2021, we announced we are pursuing plans to split Ligand into two separate, publicly traded companies with one featuring the OmniAb platform and its large and growing customer base, and the other featuring Ligand’s existing collection of core royalties and the technologies, pipeline and contracts associated with the Pelican protein expression platform and the Captisol business. Based on initial management and advisor review, an IPO and eventual distribution of OmniAb shares to Ligand shareholders is the leading option under consideration at this time. The IPO would be of newly issued shares of OmniAb, Inc. (formerly OMT), including Ab Initio computational antigen design, Icagen’s ion channel technology, xPloration high-throughput screening technology, and the suite of OmniAb animals used for antibody discovery. In an IPO, we expect OmniAb to issue less than 20% of its common stock, with us retaining the remaining interest, which would eventually be distributed to our stockholders in a manner generally intended to qualify as a tax-free transaction. Our Board of Directors has not approved a specific course of action, and we will continue to evaluate other options to optimize value and ensure flexibility to invest in growth. There can be no assurance that this process will result in us pursuing a particular transaction or consummating any such transaction. We do not expect to disclose further developments relating to this strategic review process, unless and until our Board of Directors approves a specific transaction or otherwise concludes this review. There can be no assurance that this process will result in the Company pursuing a particular transaction or consummating any such transaction.