| Cover Page - USD ($) $ in Millions | 12 Months Ended | | |
| Dec. 31, 2022 | Mar. 13, 2023 | Jun. 30, 2022 |
| Document Information [Line Items] | | | |
| Document Type | 10-K/A | | |
| Amendment Flag | true | | |
| Document Period End Date | Dec. 31, 2022 | | |
| Document Fiscal Year Focus | 2022 | | |
| Document Fiscal Period Focus | FY | | |
| Trading Symbol | ATNX | | |
| Entity Registrant Name | ATHENEX, INC. | | |
| Entity Central Index Key | 0001300699 | | |
| Current Fiscal Year End Date | --12-31 | | |
| Entity Well-known Seasoned Issuer | No | | |
| Entity Current Reporting Status | Yes | | |
| Entity Voluntary Filers | No | | |
| Entity Interactive Data Current | Yes | | |
| Entity Filer Category | Non-accelerated Filer | | |
| Entity Shell Company | false | | |
| Entity Emerging Growth Company | false | | |
| Entity Small Business | true | | |
| Entity Common Stock, Shares Outstanding | | 8,663,209 | |
| Entity Public Float | | | $ 32.5 |
| Entity Incorporation, State or Country Code | DE | | |
| Entity File Number | 001-38112 | | |
| Entity Tax Identification Number | 43-1985966 | | |
| Entity Address, Address Line One | 1001 Main Street | | |
| Entity Address, Address Line Two | Suite 600 | | |
| Entity Address, City or Town | Buffalo | | |
| Entity Address, State or Province | NY | | |
| Entity Address, Country | US | | |
| Entity Address, Postal Zip Code | 14203 | | |
| City Area Code | 716 | | |
| Local Phone Number | 427-2950 | | |
| Title of 12(b) Security | Common Stock, par value $0.001 per share | | |
| Security Exchange Name | NASDAQ | | |
| Document Annual Report | true | | |
| Document Transition Report | false | | |
| ICFR Auditor Attestation Flag | false | | |
| Amendment Description | Athenex, Inc. (the “Company,” “we,” “us,” or “our”) is filing this Amendment No. 1 (the “Amendment”) to our Annual Report on Form 10-K (the “Annual Report”) filed with the Securities and Exchange Commission (the “SEC”) for the sole purpose of providing the information required in Part III of our Annual Report within 120 days of the end of our 2022 fiscal year. The originally filed Annual Report incorporated the Part III information by reference to our Proxy Statement for our 2023 Annual Meeting of Stockholders (the “Annual Meeting”) to be filed within 120 days of the end of our 2022 fiscal year. The Annual Meeting has not been scheduled yet, and, accordingly, the Company’s Proxy Statement relating to such Annual Meeting will not be filed within 120 days of the end of our 2022 fiscal year. Except as described above, this Amendment does not amend any other information set forth in the originally filed Annual Report, and the Company has not updated disclosures included therein to reflect any subsequent events. This Amendment should be read in conjunction with the originally filed Annual Report. | | |
| Auditor Name | Deloitte & Touche LLP | | |
| Auditor Firm ID | 34 | | |
| Auditor Location | Williamsville, New York | | |
