| Document and Entity Information | Oct. 15, 2021 |
| Cover [Abstract] | |
| Entity Registrant Name | Cornerstone OnDemand Inc |
| Amendment Flag | false |
| Entity Central Index Key | 0001401680 |
| Current Fiscal Year End Date | --12-31 |
| Document Type | 8-K |
| Document Period End Date | Oct. 15, 2021 |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-35098 |
| Entity Tax Identification Number | 13-4068197 |
| Entity Address, Address Line One | 1601 Cloverfield Blvd. |
| Entity Address, Address Line Two | Suite 620 South |
| Entity Address, City or Town | Santa Monica |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 90404 |
| City Area Code | (310) |
| Local Phone Number | 752-0200 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, par value $0.0001 per share |
| Trading Symbol | CSOD |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
