Fair Value Measurements - Additional Information (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair value measurements, inter-transfers between levels	$ 0	$ 0

Fair value measurements inter transfers between levels.

No definition available.

Name:	cbz_FairValueMeasurementsInterTransfersBetweenLevels
Namespace Prefix:	cbz_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration