Document and Entity Information |
Feb. 12, 2026 |
|---|---|
| Cover [Abstract] | |
| Document Type | 8-K/A |
| Amendment Flag | true |
| Document Period End Date | Feb. 12, 2026 |
| Entity Registrant Name | Alkermes plc. |
| Entity Central Index Key | 0001520262 |
| Entity Emerging Growth Company | false |
| Entity File Number | 001-35299 |
| Entity Incorporation, State or Country Code | L2 |
| Entity Tax Identification Number | 98-1007018 |
| Entity Address, Address Line One | Connaught House |
| Entity Address, Address Line Two | 1 Burlington Road |
| Entity Address, City or Town | Dublin 4 |
| Entity Address, Country | IE |
| Entity Address, Postal Zip Code | D04 C5Y6 |
| City Area Code | 353 |
| Local Phone Number | 1-772-8000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Ordinary shares, $0.01 par value |
| Trading Symbol | ALKS |
| Security Exchange Name | NASDAQ |
| Amendment Description | On February 12, 2026, Alkermes plc (the “Company”) filed a Current Report on Form 8-K (the “Original Form 8-K”), reporting, among other items, that the Company completed the previously announced acquisition of the entire issued and outstanding ordinary share capital of Avadel Pharmaceuticals plc (“Avadel”) and Avadel became a wholly owned subsidiary of the Company (the “Acquisition”). This Amendment No. 1 on Form 8-K/A (this “Form 8-K/A”) amends and supplements Item 9.01 of the Original Form 8-K to provide the financial statements and pro forma financial information required by Items 9.01(a) and (b) of Form 8-K. Such financial information was excluded from the Original Form 8-K in reliance on the instructions to such items. This Form 8-K/A does not amend any other item of the Original Form 8-K. |