| Document and Entity Information | Nov. 05, 2019 |
| Cover [Abstract] | |
| Entity Address, State or Province | NY |
| Amendment Flag | false |
| Entity Central Index Key | 0001567514 |
| Document Type | 8-K |
| Document Period End Date | Nov. 5, 2019 |
| Entity Registrant Name | Intra-Cellular Therapies, Inc. |
| Entity File Number | 001-36274 |
| Entity Incorporation State Country Code | DE |
| Entity Tax Identification Number | 36-4742850 |
| Entity Address, Address Line One | 430 East 29th Street |
| Entity Address, City or Town | New York |
| Entity Address, Postal Zip Code | 10016 |
| City Area Code | (646) |
| Local Phone Number | 440-9333 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock |
| Trading Symbol | ITCI |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
