| Cover | Jun. 30, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Jun. 30, 2021 |
| Entity Registrant Name | CBIZ, Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 1-32961 |
| Entity Tax Identification Number | 22-2769024 |
| Entity Address, Address Line One | 6050 Oak Tree Boulevard, South, Suite 500 |
| Entity Address, City or Town | Cleveland |
| Entity Address, State or Province | OH |
| Entity Address, Postal Zip Code | 44131 |
| City Area Code | 216 |
| Local Phone Number | 447-9000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock per value $0.01 per share |
| Trading Symbol | CBZ |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Amendment Flag | false |
| Entity Central Index Key | 0000944148 |
