| Document and Entity Information | Oct. 30, 2023 |
| Cover [Abstract] | |
| Document Type | 8-K/A |
| Amendment Flag | true |
| Document Period End Date | Oct. 30, 2023 |
| Entity Registrant Name | Aileron Therapeutics, Inc. |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-38130 |
| Entity Tax Identification Number | 13-4196017 |
| Entity Address Address Line 1 | 738 Main Street |
| Entity Address Address Line 2 | #398 |
| Entity Address City Or Town | Waltham |
| Entity Address State Or Province | MA |
| Entity Address Postal Zip Code | 02451 |
| City Area Code | 617 |
| Local Phone Number | 995-0900 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, $0.001 par value per share |
| Trading Symbol | ALRN |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Amendment Description | On October 31, 2023, Aileron Therapeutics, Inc., a Delaware corporation (“Aileron” or the “Company”) filed with the Securities and Exchange Commission a Current Report on Form 8-K (the “Original Report”) to report that, among other things, the Company acquired Lung Therapeutics, Inc., a Texas corporation (“Lung”), pursuant to that certain Agreement and Plan of Merger, dated October 31, 2023 (the “Merger Agreement”), by and among Aileron, AT Merger Sub I, Inc., a Delaware corporation and a wholly owned subsidiary of Aileron (“First Merger Sub”), AT Merger Sub II, LLC, a Delaware limited liability company and wholly owned subsidiary of Aileron (“Second Merger Sub”), and Lung. Pursuant to the Merger Agreement, First Merger Sub merged with and into Lung, pursuant to which Lung was the surviving entity and became a wholly owned subsidiary of Aileron (the “First Merger”). Immediately following the First Merger, Lung merged with and into Second Merger Sub, pursuant to which Second Merger Sub was the surviving entity (the “Second Merger,” together with the First Merger, the “Merger”).This Current Report on Form 8-K/A is being filed by the Company to amend the Original Report solely to provide the financial statement and financial information required by Item 9.01 of Form 8-K that were not filed with the Original Report.Except as provided herein, the disclosures contained in this Current Report on Form 8-K/A have not been updated to reflect events, results or developments that have occurred since the filing of the Original Report. This Current Report on Form 8-K/A should be read in conjunction with the Original Report, which provides a more complete description of the Merger. |
| Entity Central Index Key | 0001420565 |
