Restructuring and Severance - Summary of Restructuring Activity by Business Segment (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring Reserve [Roll Forward]
Beginning balance	$ 6.7	$ 9.8	$ 2.9		$ 2.9
Charges	0.8	0.4	15.2	$ 1.3	16.4	$ 6.4
Utilizations	(2.5)	(3.5)	(8.3)
Ending balance	5.0	6.7	9.8		5.0
Operating Segments [Member] \| Entertainment and Communications [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	6.5	9.6	2.4		2.4
Charges	0.0	0.0	14.8
Utilizations	(1.6)	(3.1)	(7.6)
Ending balance	4.9	6.5	9.6		4.9
Operating Segments [Member] \| IT Services and Hardware [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.1	0.2	0.5		0.5
Charges	0.8	0.3	0.4
Utilizations	(0.9)	(0.4)	(0.7)
Ending balance	0.0	0.1	0.2		0.0
Corporate, Non-Segment [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.1	0.0	0.0		0.0
Charges	0.0	0.1	0.0
Utilizations	0.0	0.0	0.0
Ending balance	$ 0.1	$ 0.1	$ 0.0		$ 0.1

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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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
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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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.

+ Details

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