| Document and Entity Information | Jan. 11, 2021 |
| Document and Entity Information [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Jan. 11, 2021 |
| Entity File Number | 001-35969 |
| Entity Registrant Name | PTC THERAPEUTICS, INC. |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 04-3416587 |
| Entity Address, Address Line One | 100 Corporate Court |
| Entity Address, City or Town | South Plainfield |
| Entity Address, State or Province | NJ |
| Entity Address, Postal Zip Code | 07080 |
| City Area Code | 908 |
| Local Phone Number | 222-7000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.001 par value per share |
| Trading Symbol | PTCT |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001070081 |
| Amendment Flag | false |
