Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Licensing Agreements The Company has licensed technology for use in its diagnostic tests. In addition to the milestone payments required by these agreements, individual license agreements generally provide for ongoing royalty payments ranging from 2.0% to 7.0% on net sales of products which incorporate licensed technology, as defined in such agreements. Royalties are accrued when incurred and recorded in costs of revenue in the accompanying statements of operations. Supply Agreements In August 2024, the Company amended a supply agreement with one supplier for reagents, which includes pricing terms and minimum purchase commitments, through December 31, 2025, for new consumable products related to the Company's launch of the Anti-RA33 IgA, Anti-RA33 IgG and Anti-RA33 IgM biomarkers. The aggregate minimum annual purchase commitment related to such agreement for the year ending December 31, 2025 is $10.4 million. Collaboration Obligations In May 2021, the Company entered into an exclusive license agreement with Allegheny Health Network Research Institute (AHN), pursuant to which the Company is required to pay AHN a collaboration fee of $0.4 million per year. Collaboration expenses under the master research collaboration agreement were $0.3 million for each of the years ended December 31, 2024 and 2023. Collaboration expenses under the AHN collaboration are included in research and development expenses in the accompanying statements of operations. Contingencies In the normal course of business, the Company enters into contracts and agreements that contain a variety of representations and warranties and provide for general indemnifications; including for subpoenas and other civil investigative demands, from governmental agencies, Medicare or Medicaid and managed care organizations reviewing billing practices or requesting comment on allegations of billing irregularities that are brought to their attention through billing audits or third parties. The Company's exposure under these agreements is unknown because it involves claims that may be made against the Company in the future, but have not yet been made or that the Company believes to be immaterial. The Company accrues a liability for such matters when it is probable that future expenditures will be made and such expenditures can be reasonably estimated. Litigation From time to time, the Company may be subject to various legal proceedings that arise in the ordinary course of business activities. The Company does not believe the outcome of any such matters as of December 31, 2024 will have a material effect on its financial position or results of operations. In October 2023, the Company resolved an investigation with the U.S. Attorney’s Office for the District of Massachusetts that was initiated by a qui tam lawsuit (the October 2023 Lawsuit). Pursuant to a settlement agreement entered into by and between the Company and the U.S. Department of Justice (the Settlement Agreement), the Company made a single lump-sum remittance to the government in the amount of $0.7 million, including interest, in connection with specimen processing arrangements that Exagen historically had with physicians. The U.S. Attorney’s Office dismissed this “covered conduct” in the October 2023 Lawsuit with prejudice, while non-covered conduct was dismissed without prejudice. The Department of Justice excused itself from the case in connection with the settlement. In November 2023, the complaint was unsealed by the court and served on Exagen by the relator. Exagen filed a motion to dismiss the complaint. In December 2023, the Company's insurance carrier provided reimbursement for certain defense costs the Company incurred in the October 2023 Lawsuit. In February 2024, the relator filed a motion for leave to amend the complaint. Exagen opposed this motion, and all motions are still pending. The Company cannot predict when these matters will be resolved, the outcome of these matters, or their potential impact, which may materially and adversely affect the Company's business, prospects, and financial condition. The Company intends to vigorously defend against the claims being asserted in the complaint. The Company's participation in federal healthcare programs is not affected by the Settlement Agreement.