| Document and Entity Information | Oct. 28, 2019 |
| Cover [Abstract] | |
| Current Fiscal Year End Date | --12-31 |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Oct. 28, 2019 |
| Entity Registrant Name | Medidata Solutions, Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-34387 |
| Entity Tax Identification Number | 13-4066508 |
| Entity Address, Address Line One | 350 Hudson Street, 9th Floor |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10014 |
| City Area Code | 212 |
| Local Phone Number | 918-1800 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001453814 |
| Title of 12(b) Security | Common stock, par value $0.01 |
| Trading Symbol | MDSO |
| Security Exchange Name | NASDAQ |
