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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-Name Accounting Standards Codification
-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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenue	$ 294.0	$ 299.2	$ 572.2	$ 588.1
Operating income	20.9	27.4	15.6	57.0
Expenditures for long-lived assets		59.2	105.2	121.6
Depreciation and amortization	47.0	44.8	92.8	88.2
Assets	1,481.7		1,481.7		$ 1,541.0
Entertainment and Communications [Member]
Segment Reporting Information [Line Items]
Revenue	201.4	192.5	396.7	382.8
Operating income	26.4	27.2	24.8	54.9
Expenditures for long-lived assets	48.0	55.3	97.5	115.6
Depreciation and amortization	43.2	41.6	85.2	81.8
Assets	1,111.8		1,111.8		1,093.5
IT Services and Hardware [Member]
Segment Reporting Information [Line Items]
Revenue	96.0	109.8	182.2	212.3
Operating income	0.6	6.9	3.1	14.1
Expenditures for long-lived assets		3.8		5.8
Depreciation and amortization	3.7	3.2	7.5	6.4
Assets	94.7		94.7		60.0
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Operating income	(6.1)	(6.7)	(12.3)	(12.0)
Expenditures for long-lived assets	0.0	0.1	0.0	0.2
Depreciation and amortization	0.1	0.0	0.1	0.0
Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Revenue	(3.4)	(3.1)	(6.7)	(7.0)
Intersegment Elimination [Member] \| Entertainment and Communications [Member]
Segment Reporting Information [Line Items]
Revenue	0.5	0.2	0.9	0.6
Intersegment Elimination [Member] \| IT Services and Hardware [Member]
Segment Reporting Information [Line Items]
Revenue	2.9	2.9	5.8	6.4
Intersegment Elimination [Member] \| Corporate Segment [Member]
Segment Reporting Information [Line Items]
Assets	275.2		275.2		$ 387.5
Sales [Member] \| Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Revenue	3.4	$ 3.1	6.7	$ 7.0
Expenditures for Long-Lived Assets, Including Acquisitions of Businesses [Member]
Segment Reporting Information [Line Items]
Expenditures for long-lived assets	50.5		114.8
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	$ 2.5		$ 17.3