Restructuring Charges (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Restructuring Reserve [Roll Forward]
Beginning balance	$ 4.9	$ 14.3	$ 11.9
Restructuring charges	6.0	(0.4)	13.5
Utilizations	(9.8)	(9.0)	(11.1)
Ending balance	1.1	4.9	14.3
Restructuring liabilities included in other current liabilities	0.9	4.9
Restructuring liabilities included in other noncurrent liabilities	0.2
Entertainment and Communications [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	3.9	10.5	8.6
Restructuring charges	1.6	(0.5)	9.1
Utilizations	(4.7)	(6.1)	(7.2)
Ending balance	0.8	3.9	10.5
IT Services and Hardware [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.3	0.8	0.5
Restructuring charges	2.8	0.0	0.7
Utilizations	(2.8)	(0.5)	(0.4)
Ending balance	0.3	0.3	0.8
Corporate Segment [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.7	3.0	2.8
Restructuring charges	1.6	0.1	3.7
Utilizations	(2.3)	(2.4)	(3.5)
Ending balance	0.0	0.7	3.0
Employee Severance [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	3.0	8.4	6.5
Restructuring charges	3.3	1.0	9.0
Utilizations	(6.1)	(6.4)	(7.1)
Ending balance	0.2	3.0	8.4
Lease Abandonment [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	1.8	5.8	5.2
Restructuring charges	0.3	(1.4)	3.9
Utilizations	(1.3)	(2.6)	(3.3)
Ending balance	0.8	1.8	5.8
Contract Terminations [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.1	0.1	0.2
Restructuring charges	2.4	0.0	0.6
Utilizations	(2.4)	0.0	(0.7)
Ending balance	$ 0.1	$ 0.1	$ 0.1

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.P.3)
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-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=27011515&loc=d3e140904-122747

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section P
-Subsection 3, 4

+ Details

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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://www.xbrl.org/2003/role/presentationRef
-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=27011515&loc=d3e140904-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section P
-Subsection 3, 4

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section P
-Subsection 4

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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.

+ References

+ Details

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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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