Segment Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2025 USD ($) segment	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)
Segment Information
Number of reportable segments | segment	2
Accumulated deficit	$ 917,946		$ 902,861
Total revenue	1,455	$ 2,398
Total research and development	11,584	9,845
General and administrative	6,139	6,844
Licensing	1,010	1,031
Revaluation of contingent consideration	300	2,800
Segment operating loss	(18,084)	(18,931)
Other income	2,999	1,990
Loss before income taxes	(15,085)	(16,941)
Operating Segments | Therapeutics Segment
Segment Information
Total revenue	1,010	1,741
Research and development project spend	7,268	4,699
Personnel	2,927	4,702
Other research and development expense	1,613	677
Total research and development	11,808	10,078
Licensing	1,010	1,031
Revaluation of contingent consideration	300	2,800
Segment operating loss	(12,108)	(12,168)
Operating Segments | Contract Research Segment
Segment Information
Total revenue	445	657
Cost of revenue	3,717	4,241
General and administrative	900	1,108
Segment operating loss	(737)	(1,027)
Operating Segments | Bosakitug | Therapeutics Segment
Segment Information
Research and development project spend	3,384
Operating Segments | ATI-2138 | Therapeutics Segment
Segment Information
Research and development project spend	1,808	63
Operating Segments | ATI-052 | Therapeutics Segment
Segment Information
Research and development project spend	619
Operating Segments | Lepzacitinib | Therapeutics Segment
Segment Information
Research and development project spend		1,073
Operating Segments | Zunsemetinib | Therapeutics Segment
Segment Information
Research and development project spend	111	2,023
Operating Segments | Discovery | Therapeutics Segment
Segment Information
Research and development project spend	1,346	1,540
Intersegment Eliminations
Segment Information
Total revenue	(3,435)	(3,665)
Cost of revenue	(3,211)	(3,432)
Total research and development	(224)	(233)
Intersegment Eliminations | Contract Research Segment
Segment Information
Total revenue	3,435	3,665
Total
Segment Information
Total revenue	1,455	2,398
Cost of revenue	506	809
Research and development project spend	7,268	4,699
Personnel	2,927	4,702
Other research and development expense	1,613	677
Total research and development	11,584	9,845
General and administrative	900	1,108
Licensing	1,010	1,031
Revaluation of contingent consideration	300	2,800
Segment operating loss	(12,845)	(13,195)
Total | Bosakitug
Segment Information
Research and development project spend	3,384
Total | ATI-2138
Segment Information
Research and development project spend	1,808	63
Total | ATI-052
Segment Information
Research and development project spend	619
Total | Lepzacitinib
Segment Information
Research and development project spend		1,073
Total | Zunsemetinib
Segment Information
Research and development project spend	111	2,023
Total | Discovery
Segment Information
Research and development project spend	1,346	1,540
Reconciliation of segment
Segment Information
General and administrative	5,239	5,736
Other income	$ 2,999	$ 1,990