Debt and Other Financing Arragnements - Company's Debt (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Current portion of long-term debt	$ 18.4	$ 7.5
Receivables facility amount outstanding	0.0	89.5
Long-term debt, less current portion	1,729.3	1,199.1
Net unamortized premium	1.9	8.5
Debt Issuance Costs, Noncurrent, Net	22.3
Debt and Capital Lease Obligations	$ 1,747.7	1,206.6
Senior Notes due 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	8.25%
Senior Subordinated Notes due 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	8.75%
Senior Notes due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	8.38%
Various Cincinnati Bell Telephone Notes [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion	$ 87.9	87.9
Capital lease Obligations and Other Debt [Member]
Debt Instrument [Line Items]
Current portion of long-term debt	12.4	7.5
Long-term debt, less current portion	70.5	62.0
Tranche B Term Loan due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion	0.0	315.8
Tranche B Term Loan due 2024 [Member]
Debt Instrument [Line Items]
Current portion of long-term debt	6.0	0.0
Long-term debt, less current portion	$ 594.0	0.0
Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.25%
Long-term debt, less current portion	$ 22.3	22.3
Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.00%
Long-term debt, less current portion	$ 625.0	625.0
8% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	8.00%
Long-term debt, less current portion	$ 350.0	0.0
Long-term debt, less current portion, before deducting unamortized discount or premium [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion	1,749.7	1,202.5
Long-Term Debt, Less Current Portion [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Noncurrent, Net	22.3	11.9
Long-Term Debt, Less Current Portion [Member] \| Long-Term Debt, Less Current Portion [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion	$ 1,729.3	$ 1,199.1

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

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

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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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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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