Number of days moving average share price calculation.

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- Definition

Senior leverage ratio.

+ References

No definition available.

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- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

+ Details

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- Definition

Description of voting rights of common stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

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- Definition

Including the current and noncurrent portions, the carrying value of convertible subordinated debt, as of the balance sheet date, initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. This form of debt can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder, and places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

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-Topic 210

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-Section S99

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Article 5

-Subsection 20, 22

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- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

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-Topic 230

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-Section 50

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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- Definition

The cash outflow to reacquire common stock during the period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

+ References

No definition available.

+ Details

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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- Definition

Description of share repurchase program, including accounting treatment.

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-Topic 505

-SubTopic 30

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Common Stock - Additional Information (Detail) (USD $)	12 Months Ended			0 Months Ended
Common Stock - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Aug. 30, 2013	Jul. 01, 2013	Sep. 27, 2010	Sep. 14, 2010
Schedule Of Common Stock [Line Items]
Common stock, shares authorized	250,000,000us-gaap_CommonStockSharesAuthorized	250,000,000us-gaap_CommonStockSharesAuthorized
Common stock, par value	$ 0.01	$ 0.01
Common stock voting rights	One vote for each share held on all matters submitted to a vote of stockholders. There are no cumulative voting rights with respect to the election of directors.
Senior leverage ratio	3.0cbz_SeniorLeverageRatio
Share repurchase program, description	Under CBIZ's credit facility (described in Note 8) share repurchases are unlimited when total leverage is less than 3.0. When leverage is greater than 3.0, the annual share repurchase is limited to $25.0 million.
Stock repurchase program authorized to be repurchased	3,200,000	0	1,000,000
Payment for acquisition of treasury stock	$ 28,137,000	$ 26,468,000	$ 5,716,000
2010 Convertible Senior Subordinated Notes [Member]
Schedule Of Common Stock [Line Items]
Shares issued in exchange for partial retirement of debt	1,500,000
Partial Extinguishment of debt	32,400,000
Cash portion of retirement	30,600,000
Convertible Senior Subordinated Notes	130,000,000					130,000,000
Maximum [Member]
Schedule Of Common Stock [Line Items]
Annual share repurchase limit	25,000,000
Westbury Agreement [Member]
Schedule Of Common Stock [Line Items]
Common stock, par value	$ 7.25
Stock repurchase program authorized to be repurchased							7,700,000
MMP [Member]
Schedule Of Common Stock [Line Items]
Percentage of Holding				50.00%
Common stock, per share amount				$ 6.65
Payment for acquisition of treasury stock				25,700,000
MMP [Member] \| Westbury Agreement [Member]
Schedule Of Common Stock [Line Items]
Stock repurchase program authorized to be repurchased		3,900,000
Percentage of Holding		50.00%		50.00%
Common stock, per share amount		$ 6.65		$ 6.65
Payment for acquisition of treasury stock		$ 25,700,000		$ 25,700,000
Number of days moving average share price calculation				60 days	60 days