Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Revenue	$ 299.8	$ 301.4	$ 878.5	$ 866.6
Operating income (loss)	36.2	47.8	103.0	145.5
Expenditures for long-lived assets	73.2	45.3	205.7	121.1
Depreciation and amortization	35.8	32.3	102.4	94.4
Assets	1,460.2		1,460.2		$ 1,820.7
Entertainment and Communications [Member]
Segment Reporting Information [Line Items]
Revenue	185.4	184.0	555.9	552.3
Operating income (loss)	30.4	43.0	101.8	144.4
Expenditures for long-lived assets	69.4	41.8	193.5	106.1
Depreciation and amortization	32.6	29.3	93.1	85.6
Assets	942.3		942.3		833.2
IT Services and Hardware [Member]
Segment Reporting Information [Line Items]
Revenue	117.0	120.0	330.9	323.5
Operating income (loss)	8.2	8.1	15.5	16.3
Expenditures for long-lived assets	3.8	3.5	12.1	8.5
Depreciation and amortization	3.1	3.0	9.2	8.6
Assets	68.6		68.6		61.4
Discontinued Operations [Member]
Segment Reporting Information [Line Items]
Assets	0.0		0.0		49.3
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Operating income (loss)	(2.4)	(3.3)	(14.3)	(15.2)
Expenditures for long-lived assets	0.0	0.0	0.1	0.0
Depreciation and amortization	0.1	0.0	0.1	0.2
Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Revenue	(2.6)	(2.6)	(8.3)	(9.2)
Intersegment Elimination [Member] \| Entertainment and Communications [Member]
Segment Reporting Information [Line Items]
Revenue	0.2	0.3	0.9	0.8
Intersegment Elimination [Member] \| IT Services and Hardware [Member]
Segment Reporting Information [Line Items]
Revenue	2.4	2.3	7.4	8.4
Intersegment Elimination [Member] \| Corporate Segment [Member]
Segment Reporting Information [Line Items]
Assets	449.3		449.3		$ 876.8
Sales [Member] \| Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Revenue	$ 2.6	$ 2.6	$ 8.3	9.2
Continuing Operations [Member]
Segment Reporting Information [Line Items]
Expenditures for long-lived assets				$ 114.6

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 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.18)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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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.

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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.

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