Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Current portion of long-term debt	$ 18.3	$ 18.4
Receivables Facility	144.2	0.0
Long-term debt, less current portion	1,909.4	1,729.3
Credit Agreement - Revolving Credit Facility	50.0	0.0
Net unamortized premium	1.7	1.9
Unamortized note issuance costs	(28.2)	(22.3)
Total debt	1,927.7	1,747.7
Tranche B Term Loan due 2024 [Member]
Debt Instrument [Line Items]
Current portion of long-term debt	6.0	6.0
Long-term debt, less current portion	594.0	594.0
Capital lease Obligations and Other Debt [Member]
Debt Instrument [Line Items]
Current portion of long-term debt	12.3	12.4
Long-term debt, less current portion	62.5	70.5
Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Senior Notes, Noncurrent	$ 22.3	22.3
Debt Instrument, Interest Rate, Stated Percentage	7.25%
Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Senior Notes, Noncurrent	$ 625.0	625.0
Debt Instrument, Interest Rate, Stated Percentage	7.00%
8% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Senior Notes, Noncurrent	$ 350.0	350.0
Debt Instrument, Interest Rate, Stated Percentage	8.00%
Various Cincinnati Bell Telephone Notes [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion	$ 87.9	87.9
Long-term debt, less current portion, before deducting unamortized discount or premium and before deducting unamortized note issuance costs [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion	$ 1,935.9	$ 1,749.7

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

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- Definition

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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

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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.

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- Definition

Amount, after accumulated amortization, of debt discount (premium).

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- Definition

Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

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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- Definition

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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