Debt and Other Financing Arrangements - Company's Debt (Details) - USD ($)	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Current portion of long-term debt	$ 20,200,000		$ 18,400,000
Finance Lease, Liability, Current	800,000		0
Capital Lease Obligations, Current	13,400,000		12,400,000
Receivables facility amount outstanding	176,600,000		0
Long-term Line of Credit	18,000,000		0
Long-term debt, less current portion	1,909,600,000		1,729,300,000
Finance Lease, Liability, Noncurrent	2,300,000		0
Capital Lease Obligations, Noncurrent	60,500,000		70,500,000
Net unamortized premium	1,700,000		1,900,000
Debt Issuance Costs, Noncurrent, Net	27,200,000		22,300,000
Debt and Capital Lease Obligations	$ 1,929,800,000		1,747,700,000
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	$ 87,900,000		87,900,000
Tranche B Term Loan due 2024 [Member]
Debt Instrument [Line Items]
Current portion of long-term debt	6,000,000		6,000,000
Long-term debt, less current portion	$ 592,500,000		594,000,000
Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.25%
Senior Notes, Noncurrent	$ 22,300,000		22,300,000
Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.00%
Senior Notes, Noncurrent	$ 625,000,000		625,000,000
8% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	8.00%
Senior Notes, Noncurrent	$ 350,000,000	$ 350,000,000	350,000,000
Long-term debt, less current portion, before deducting unamortized discount or premium [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion	1,935,100,000		1,749,700,000
Long-Term Debt, Less Current Portion [Member] \| Long-Term Debt, Less Current Portion [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion	$ 1,909,600,000		$ 1,729,300,000

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

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after 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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Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

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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 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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