Financial Instruments - Interest Rate Swaps (Details)	Mar. 31, 2022 USD ($) swap
Interest rate swaps
Debt Securities, Available-for-sale [Line Items]
Number of interest rate swaps outstanding \| swap	4
Interest rate swap, May 2022 expiration
Debt Securities, Available-for-sale [Line Items]
Notional amount	$ 20,000,000
Interest rate swap, fixed interest rate	1.77%
Interest rate swap, June 2023 expiration
Debt Securities, Available-for-sale [Line Items]
Notional amount	$ 15,000,000
Interest rate swap, fixed interest rate	2.64%
Interest rate swap, April 2025 expiration
Debt Securities, Available-for-sale [Line Items]
Notional amount	$ 50,000,000
Interest rate swap, fixed interest rate	0.885%
Interest rate swap, December 2026 expiration
Debt Securities, Available-for-sale [Line Items]
Notional amount	$ 30,000,000
Interest rate swap, fixed interest rate	1.249%

Fixed interest rate related to the interest rate derivative.

No definition available.

Name:	us-gaap_DerivativeFixedInterestRate
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

+ Details

Name:	us-gaap_DerivativeNotionalAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

+ Details

Name:	us-gaap_NumberOfInterestRateDerivativesHeld
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cbz_InterestRateSwapMay2022ExpirationMember
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- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cbz_InterestRateSwapJune2023ExpirationMember
Namespace Prefix:
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- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cbz_InterestRateSwapApril2025ExpirationMember
Namespace Prefix:
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Balance Type:
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- Details

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