Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018
Debt Instrument [Line Items]
Current portion of long-term debt	$ 22.4	$ 20.2
Other Financing Arrangements, Current Portion	1.1	0.8
Capital Lease Obligations, Current	15.3	13.4
Receivables Facility	175.8	176.6
Long-term debt, less current portion	1,909.9	1,909.6
Other Financing Arrangements, Non-Current Portion	2.0	2.3
Capital Lease Obligations, Noncurrent	65.4	60.5
Credit Agreement - Revolving Credit Facility	15.0	18.0
Net unamortized premium	1.6	1.7
Unamortized note issuance costs	(26.1)	(27.2)
Total debt	1,932.3	1,929.8
Other Installment Financing Arrangements	44.3	44.6
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	$ 591.0	592.5
Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.25%
Senior Notes, Noncurrent	$ 22.3	22.3
Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.00%
Senior Notes, Noncurrent	$ 625.0	625.0
8% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	8.00%
Senior Notes, Noncurrent	$ 350.0	350.0	$ 350.0
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	1,934.4	1,935.1
Data Center Financing Arrangements [Member]
Debt Instrument [Line Items]
Other Installment Financing Arrangements	$ 4.5	$ 4.5

The current portion of the other financing arrangement liabilities (not including capital lease obligations).

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The non-current portion of the other financing arrangement liabilities (not including capital lease obligations).

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The total amount of other installment financing arrangement liabilities (not including capital lease obligations).

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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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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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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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