| Cover Page | Nov. 09, 2021 |
| Entity Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Nov. 9, 2021 |
| Entity Registrant Name | HEALTH CATALYST, INC. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-38993 |
| Entity Tax Identification Number | 45-3337483 |
| Entity Address, Address Line One | 10897 South River Front Parkway |
| Entity Address, Address Line Two | #300 |
| Entity Address, City or Town | South Jordan |
| Entity Address, State or Province | UT |
| Entity Address, Postal Zip Code | 84095 |
| City Area Code | 801 |
| Local Phone Number | 708-6800 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, par value $0.001 per share |
| Trading Symbol | HCAT |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Amendment Flag | false |
| Entity Central Index Key | 0001636422 |
| Former Address | |
| Entity Information [Line Items] | |
| Entity Address, Address Line One | Not Applicable |
