Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Segment Reporting Information [Line Items]
Revenue	$ 312.4	$ 299.8	$ 900.5	$ 878.5
Operating income (loss)	25.5	36.2	82.5	103.0
Expenditures for long-lived assets	67.2	73.2	188.8	205.7
Depreciation and amortization	46.5	35.8	134.7	102.4
Assets	1,529.9		1,529.9		$ 1,446.4
Entertainment and Communications [Member]
Segment Reporting Information [Line Items]
Revenue	193.0	185.4	575.8	555.9
Operating income (loss)	21.1	30.4	76.0	101.8
Expenditures for long-lived assets	63.1	69.4	178.7	193.5
Depreciation and amortization	43.0	32.6	124.8	93.1
Assets	1,062.4		1,062.4		982.5
IT Services and Hardware [Member]
Segment Reporting Information [Line Items]
Revenue	122.9	117.0	335.2	330.9
Operating income (loss)	7.8	8.2	21.9	15.5
Expenditures for long-lived assets	4.1	3.8	9.9	12.1
Depreciation and amortization	3.4	3.1	9.8	9.2
Assets	59.1		59.1		58.0
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Operating income (loss)	(3.4)	(2.4)	(15.4)	(14.3)
Expenditures for long-lived assets	0.0	0.0	0.2	0.1
Depreciation and amortization	0.1	0.1	0.1	0.1
Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Revenue	(3.5)	(2.6)	(10.5)	(8.3)
Intersegment Elimination [Member] \| Entertainment and Communications [Member]
Segment Reporting Information [Line Items]
Revenue	0.4	0.2	1.0	0.9
Intersegment Elimination [Member] \| IT Services and Hardware [Member]
Segment Reporting Information [Line Items]
Revenue	3.1	2.4	9.5	7.4
Intersegment Elimination [Member] \| Corporate Segment [Member]
Segment Reporting Information [Line Items]
Assets	408.4		408.4		$ 405.9
Sales [Member] \| Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Revenue	$ 3.5	$ 2.6	$ 10.5	$ 8.3

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ 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)
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Paragraph 13
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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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