Amortized discount at annual effective rate.

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Discount, period of issuance.

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Line of credit facility maturity period.

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Number of group of participating banks.

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Primary debt arrangements.

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Remaining period for amortization discount.

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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.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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The price per share of the conversion feature embedded in the debt instrument.

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Earliest date when the debt instrument can be converted into equity, in CCYY-MM-DD format.

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Description of the conversion terms of a debt instrument which may include the conversion ratio (including all potential conversion ratios if contingently adjustable), type of debt or equity security into which the debt is convertible, the dollars of debt or the number of shares into which the instrument is convertible (or potentially convertible into), the conversion period, any contingencies associated with the conversion terms, and the existence and amount of a beneficial conversion feature.

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instruments must exceed threshold percentage for a specified number of trading days to trigger conversion feature, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

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No definition available.

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Borrowing Arrangements - Additional Information (Detail) (USD $)	0 Months Ended	6 Months Ended
	Sep. 27, 2010	Jun. 30, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Primary debt arrangements		2
Unsecured credit facility		$ 275,000,000
Group of participating banks		7
Outstanding balance under credit facility		81,200,000	48,500,000
Approximately available funds under credit facility		58,600,000
Maturity date of credit facility		2015-06
Letter of Credit and Performance Guarantee [Member]
Debt Instrument [Line Items]
Outstanding letters of credit and performance guarantees		4,400,000
2010 Convertible Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Convertible Senior Subordinated Notes	130,000,000	130,000,000
Unsecured credit facility		275,000,000
Interest rate on Notes	4.875%
Notes payable terms		Semi-annually in arrears on April 1 and October 1
Maturity date of Notes	Oct. 01, 2015
Beginning date of notes	Jul. 01, 2015
Percentage of Common stock	135.00%
Common stock convertible price	$ 7.41
Notes, convertible, threshold trading days		30 days
Notes, convertible, terms of conversion feature		The holders of the 2010 Notes may convert their 2010 Notes beginning July 1, 2015, or earlier, if the market price per share of CBIZ common stock exceeds 135% of the initial conversion price of $7.41 for at least 20 days during the period of 30 consecutive trading days ending on the final trading day of the preceding quarter.
Amortized discount at annual effective rate	7.50%
Discount, period of issuance	5 years
Remaining period for amortization of discount		15 months
Principal amount of notes		130,000,000	130,000,000
2010 Convertible Senior Subordinated Notes [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Notes, convertible, threshold trading days		20 days
2006 Convertible Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Interest rate on Notes		3.125%
Notes payable terms		Semi-annually in arrears on each June 1 and December 1
Maturity date of Notes		Jun. 01, 2026
Principal amount of notes		$ 750,000