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
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-Name Accounting Standards Codification
-Topic 942
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
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The aggregate net amount of depreciation, amortization, and accretion recognized during an accounting period. As a noncash item, the net amount is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ 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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The net result for the period of deducting operating expenses from operating revenues.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 230
-SubTopic 10
-Section 45
-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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
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Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenue	$ 289.2	$ 312.4	$ 861.4	$ 900.5
Operating income	12.7	25.5	28.3	82.5
Expenditures for long-lived assets	43.0	67.2	148.2	188.8
Depreciation and amortization	47.3	46.5	140.1	134.7
Assets	1,457.3		1,457.3		$ 1,541.0
Entertainment and Communications [Member]
Segment Reporting Information [Line Items]
Revenue	196.2	193.0	592.9	575.8
Operating income	25.0	21.1	49.8	76.0
Expenditures for long-lived assets	41.4	63.1	138.9	178.7
Depreciation and amortization	43.9	43.0	129.1	124.8
Assets	1,114.7		1,114.7		1,093.5
IT Services and Hardware [Member]
Segment Reporting Information [Line Items]
Revenue	96.3	122.9	278.5	335.2
Operating income	4.8	7.8	7.9	21.9
Expenditures for long-lived assets	1.6	4.1		9.9
Depreciation and amortization	3.4	3.4	10.9	9.8
Assets	85.9		85.9		60.0
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Operating income	(17.1)	(3.4)	(29.4)	(15.4)
Expenditures for long-lived assets	0.0	0.0	0.0	0.2
Depreciation and amortization	0.0	0.1	0.1	0.1
Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Revenue	(3.3)	(3.5)	(10.0)	(10.5)
Intersegment Elimination [Member] \| Entertainment and Communications [Member]
Segment Reporting Information [Line Items]
Revenue	0.4	0.4	1.3	1.0
Intersegment Elimination [Member] \| IT Services and Hardware [Member]
Segment Reporting Information [Line Items]
Revenue	2.9	3.1	8.7	9.5
Intersegment Elimination [Member] \| Corporate Segment [Member]
Segment Reporting Information [Line Items]
Assets	256.7		256.7		$ 387.5
Sales [Member] \| Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Revenue	$ 3.3	$ 3.5	10.0	$ 10.5
Expenditures for Long-Lived Assets, Including Acquisitions of Businesses [Member]
Segment Reporting Information [Line Items]
Expenditures for long-lived assets			157.8
Expenditures for Long-Lived Assets, Including Acquisitions of Businesses [Member] \| IT Services and Hardware [Member]
Segment Reporting Information [Line Items]
Expenditures for long-lived assets			$ 18.9