Restructuring and Severance - Summary of Restructuring Activity by Business Segment (Details) - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019
Restructuring Reserve [Roll Forward]
Beginning balance	$ 4.6	$ 6.8	$ 10.2
Hawaiian Telcom opening balance sheet adjustment			0.1
Restructuring Charges	1.3	1.8	3.3
Utilizations	(2.4)	(4.0)	(6.8)
Ending balance	3.5	4.6	6.8
Entertainment and Communications [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	3.8	5.7	8.6
Hawaiian Telcom opening balance sheet adjustment			0.1
Restructuring Charges	0.7	0.9	3.3
Utilizations	(1.6)	(2.8)	(6.3)
Ending balance	2.9	3.8	5.7
IT Services and Hardware [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.7	0.8	1.3
Hawaiian Telcom opening balance sheet adjustment			0.0
Restructuring Charges	0.6	0.9	0.0
Utilizations	(0.7)	(1.0)	(0.5)
Ending balance	0.6	0.7	0.8
Corporate Segment [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.1	0.3	0.3
Hawaiian Telcom opening balance sheet adjustment			0.0
Restructuring Charges	0.0	0.0	0.0
Utilizations	(0.1)	(0.2)	0.0
Ending balance	$ 0.0	$ 0.1	$ 0.3

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

No definition available.

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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.

+ References

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

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

+ References

No definition available.

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