Commitments and contingencies.

No definition available.

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- Definition

Transaction Price

+ References

No definition available.

+ Details

Name:	cbz_TransactionPrice
Namespace Prefix:	cbz_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount awarded from other party in judgment or settlement of litigation.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-4

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-9

+ Details

Name:	us-gaap_LossContingencyDamagesSoughtValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The total number of new claims filed pertaining to a loss contingency during the period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-4

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-9

+ Details

Name:	us-gaap_LossContingencyNewClaimsFiledNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of defendants named in a legal action.

+ References

+ Details

Name:	us-gaap_LossContingencyNumberOfDefendants
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
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- Details

Name:	srt_LitigationCaseAxis=cbz_MOVEitCustomerDataSecurityBreachLitigationMember
Namespace Prefix:
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COMMITMENTS AND CONTINGENCIES - Legal Proceedings (Details) $ in Millions			12 Months Ended
	Mar. 12, 2024 USD ($)	Dec. 19, 2016 USD ($)	Dec. 31, 2024 defendant claim
CBIZ Operations and former employee of CBIZ MMP
Commitments And Contingencies [Line Items]
Total transaction price		$ 200.0
Loss contingency, amount of damages awarded	$ 3.1
CBIZ Operations and former employee of CBIZ MMP \| Maximum
Commitments And Contingencies [Line Items]
Amount of damages sought (up to)		$ 177.0
MOVEit Customer Data Security Breach Litigation
Commitments And Contingencies [Line Items]
Number of claims filed \| claim			180
Number of defendants \| defendant			100