The number of days available for bank renewal of the accounts receivable securitization facility.

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The percentage of equity interests in first-tier foreign subsidiaries held by the Company and the guarantors under the Corporate Credit Agreement that acts as a security interest in securing debt outstanding under the Corporate Credit Agreement.

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The percentage of original issue discount applicable to the issuance of long-term debt.

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Represents the threshold for the Consolidated Total Leverage Ratio that triggers limitations to the company's levels of restricted payments.

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No definition available.

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Represents the threshold for the Consolidated Total Leverage Ratio where no dollar limits on restricted payments exist.

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No definition available.

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The maximum aggregate capital expenditures allowed to be incurred over the next five years, as provided for under the Company’s Corporate Credit Agreement.

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No definition available.

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The percentage of the original principal amount of long-term debt that is required to be repaid on a quarterly basis.

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The percentage of proceeds from a sale of the Company’s investment in CyrusOne that is required to be applied to mandatory prepayments under the Corporate Credit Agreement.

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No definition available.

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The amount of borrowings outstanding on the accounts receivable securitization facility as of the balance sheet date.

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No definition available.

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The maximum borrowing availability under the accounts receivable securitization facility as of the balance sheet date, based on the quantity and quality of outstanding accounts receivable.

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No definition available.

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Maximum borrowing capacity of the accounts receivable securitization facility based on the terms of the agreement.

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The maximum annual amount of restricted payments allowed when a specified threshold per the credit agreement for the Company’s Consolidated Total Leverage Ratio has been reached.

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The maximum amount of restricted payments allowed when the Company’s Consolidated Total Leverage Ratio exceeds a specified threshold per the credit agreement.

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The annual cap of proceeds from the sale of the Company’s investment in CyrusOne that may be used by the company for share buy-backs and dividend payments, subject to carryovers.

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The portion of proceeds from the sale of the Company’s investment in CyrusOne that may be used to buy back shares or pay for dividends, subject to a monetary cap.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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The average effective interest rate during the reporting period.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Maximum contractual interest rate for funds borrowed, under the debt agreement.

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Minimum contractual interest rate for funds borrowed, under the debt agreement.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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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 the fee for available but unused credit capacity under the credit facility.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Debt - Credit Facilities (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2015	Jun. 30, 2013	Sep. 30, 2013	Oct. 15, 2013	Jan. 24, 2013
Line of Credit Facility [Line Items]
Line of credit facility, maximum aggregate capital expenditures over life of the agreement			$ 937.7
Line of Credit Facility, Maximum Borrowing Capacity						125.0
Proceeds from sale of CyrusOne equity method investment	355.9		355.9	0	0
Long-Term Debt, Required Principal Payments			0.25%
Proceeds received from Tranche B Term Loan			0	536.0	525.0
Debt Instrument, Redemption Price, Percentage		104.125%
Issuance of Long-Term Debt, Original Issue Discount		0.75%		0.75%
Loss on extinguishment of debt			19.6	29.6	13.6
Write-off of debt discount			0
Restricted payments, limit when leverage ratio threshold not attained			15.0
Leverage Ratio, threshold			3.50cbb_LeverageRatiothreshold
Restricted payments, limit when leverage ratio threshold is attained			45.0
Leverage Ratio, threshold, other			3.00cbb_LeverageRatiothresholdother
Restricted Payments, Share Repurchases or Dividends, limit			15.00%
Restricted Payments, Share Repurchases or Dividends, cap			35.0
Proceeds from Sale of Equity Method Investment, Percent Required for Mandatory Debt Prepayments		100.00%	85.00%	100.00%
Equity Interests in Foreign Subsidiaries			66.00%
Line of Credit Facility, Amount Outstanding		40.0us-gaap_LineOfCredit	0us-gaap_LineOfCredit	40.0us-gaap_LineOfCredit
Line of Credit Facility, Remaining Borrowing Capacity		160.0	150.0	160.0
Line of Credit Facility, Commitment Fee Amount			0.9	1.0	1.6
Receivables facility maximum borrowing capacity			120.0				105.0
Receivables facility maximum borrowing availability			116.8
Accounts Receivable Facility, Renewal Term			364
Receivables facility amount outstanding		106.2	19.2	106.2
Letters of Credit Outstanding, Amount			6.9
Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			150.0		200.0
Standby Letters of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			30.0
Bridge Loan [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			25.0
Tranche B Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			4.00%
Debt Instrument, Face Amount		533.2	527.8	533.2				540.0
Proceeds received from Tranche B Term Loan				529.8
Tranche B Term Loan [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate			3.00%
Senior Notes due 2017 [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			8.25%
Debt Instrument, Face Amount									500.0
Accrued interest									20.6
Receivables Facilities [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Commitment Fee Amount			0.8	0.7	0.7
Debt Instrument, Interest Rate During Period			0.70%
London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum			3.50%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum			4.25%
Debt Instrument, Interest Rate, Stated Percentage			4.00%
Debt Instrument, Basis Spread on Variable Rate			1.00%
London Interbank Offered Rate (LIBOR) [Member] \| Tranche B Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum			1.00%
Debt Instrument, Basis Spread on Variable Rate			1.00%
London Interbank Offered Rate (LIBOR) [Member] \| Receivables Facilities [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate			0.50%
Base Rate [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum			2.50%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum			3.25%
Debt Instrument, Interest Rate, Stated Percentage			3.00%
Base Rate [Member] \| Tranche B Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate			2.00%
Federal Funds Rate [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate			0.50%
Federal Funds Rate [Member] \| Tranche B Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate			0.50%
Minimum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Commitment Fee Percentage			0.50%
Maximum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Commitment Fee Percentage			0.625%
CyrusOne LP [Member] \| Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity										225.0
CyrusOne LP [Member] \| Standby Letters of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity										50.0
CyrusOne LP [Member] \| Bridge Loan [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity										$ 30.0