| Document and Entity Information | Sep. 16, 2024 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Sep. 16, 2024 |
| Entity Registrant Name | Hackett Group, Inc. |
| Entity Incorporation State Country Code | FL |
| Entity File Number | 333-48123 |
| Entity Tax Identification Number | 65-0750100 |
| Entity Address Address Line 1 | 1001 Brickell Bay Drive |
| Entity Address Address Line 2 | Suite 3000 |
| Entity Address City Or Town | Miami |
| Entity Address State Or Province | FL |
| Entity Address Postal Zip Code | 33131 |
| City Area Code | 305 |
| Local Phone Number | 375-8005 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, par value $.001 per share |
| Trading Symbol | HCKT |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001057379 |
| Amendment Flag | false |
