Restructuring and Severance (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Current	$ 6.4	$ 9.6
Restructuring Reserve, Noncurrent	0.4	$ 0.6
Restructuring Reserve [Roll Forward]
Beginning balance	10.2
Hawaiian Telcom opening balance sheet adjustment	0.1
Restructuring Charges	3.3
Utilizations	(6.8)
Ending balance	6.8
Entertainment and Communications [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	8.6
Hawaiian Telcom opening balance sheet adjustment	0.1
Restructuring Charges	3.3
Utilizations	(6.3)
Ending balance	5.7
IT Services and Hardware [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	1.3
Hawaiian Telcom opening balance sheet adjustment	0.0
Restructuring Charges	0.0
Utilizations	(0.5)
Ending balance	0.8
Corporate Segment [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.3
Hawaiian Telcom opening balance sheet adjustment	0.0
Restructuring Charges	0.0
Utilizations	0.0
Ending balance	0.3
Employee Severance [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	9.5
Hawaiian Telcom opening balance sheet adjustment	0.1
Restructuring Charges	3.3
Utilizations	(6.7)
Ending balance	6.2
Lease Abandonment [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.7
Hawaiian Telcom opening balance sheet adjustment	0.0
Restructuring Charges	0.0
Utilizations	(0.1)
Ending balance	$ 0.6

The total amount of restructuring and severance payments that have occurred during the current period.

No definition available.

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- Definition

This item represents liabilities associated with restructuring or exit activities of the acquiree, existing at the acquisition date (present liabilities of the acquiree).

+ References

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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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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No definition available.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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