Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended										12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Apr. 01, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Sale of Intangible Assets											$ 0.0	$ 194.4	$ 0.0
Disposal Group, Including Discontinued Operation, Intangible Assets, Noncurrent							$ 88.2
Prepaid Expense, Current	$ 13.1				$ 10.8	$ 6.4					13.1	10.8
Gain (Loss) on Disposition of Intangible Assets				$ (112.6)							(112.6)	0.0	0.0
Gain on Liabilities and Other Assets transferred in Sale of Business Affiliate and Productive Assets			$ 15.9								15.9	0.0	0.0
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment														$ 16.0
Revenue, Net	289.3	$ 299.8	285.8	292.9	294.9	301.4	283.0	$ 282.2			1,167.8	1,161.5	1,073.4
Selling, General and Administrative Expense											219.1	204.2	187.9
Depreciation and amortization											141.6	127.6	128.4
Restructuring charges											6.0	(0.4)	13.5
Impairment of assets											0.0	4.6	0.0
Transaction costs											1.4	1.2	1.6
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property											0.8	(0.3)	(1.1)
Sale Leaseback Transaction, Current Period Gain Recognized											(6.5)	(22.9)	(3.3)
Costs and Expenses											1,039.8	984.6	933.6
Operating income (loss)	25.0	36.2	29.7	37.1	31.4	47.8	47.3	50.4			128.0	176.9	139.8
Other expense (income), net											(2.5)	(1.9)	(3.3)
Income tax expense (benefit)											159.8	81.4	(8.3)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	2.1	$ 1.0	$ 10.9	$ 48.9	(13.9)	$ (19.8)	$ (9.5)	$ 1.1			62.9	(42.1)	10.2
Disposal Group, Including Discontinued Operation, Other Assets, Current	0.0				4.7						0.0	4.7
Property, plant and equipment, net	975.5				815.4						975.5	815.4
Intangible Assets, Net (Excluding Goodwill)	0.2				0.5						0.2	0.5
Current portion of long-term debt	13.8				11.6						13.8	11.6
Accounts payable	127.4				131.6						127.4	131.6
Restructuring Reserve	0.9				4.9						0.9	4.9
Disposal Group, Including Discontinued Operation, Other Liabilities, Current	5.4				142.0						5.4	142.0
Long-term debt, less current portion	1,231.8				1,689.4						1,231.8	1,689.4
Disposal Group, Including Discontinued Operation, Liabilities, Noncurrent	0.0				102.7						0.0	102.7
Other Liabilities, Noncurrent	36.6				26.2						36.6	26.2
Liabilities	1,752.6				2,469.2						1,752.6	2,469.2
Change in Accounting Estimate, Effect of Change on Operating Results, Increase in Depreciation Expense									$ 3.0	$ 8.5		62.2
Impairment of assets											0.0	12.1	0.0
Payments for Restructuring											(9.8)	(9.0)	(11.1)
Capital expenditures											(283.6)	(182.3)	(196.9)
Repayment of debt											(531.7)	(376.5)	(530.8)
Operating lease expense											10.1	7.4	6.5
Operating Leases, Future Minimum Payments Due, Next Twelve Months	3.9										3.9
Operating Leases, Future Minimum Payments, Due in Two Years	3.7										3.7
Operating Leases, Future Minimum Payments, Due Thereafter	22.0										22.0
Operating Leases, Future Minimum Payments Due	37.0										37.0
Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Sale of Intangible Assets											0.0	194.4	0.0
Prepaid Expense, Current	0.0				3.2						0.0	3.2
Long-term Debt, Current Maturities														0.5
Long-term Debt, Excluding Current Maturities														24.8
Disposal Group, Including Discontinued Operation, Other Liabilities, Noncurrent	0.0				8.0						0.0	8.0		6.6
Disposal Group, Including Discontinued Operation, Liabilities	5.4				244.7						5.4	244.7		31.9
Revenue, Net											4.4	132.8	201.5
Cost of Goods and Services Sold											12.0	66.9	102.3
Selling, General and Administrative Expense											2.2	19.5	33.6
Depreciation and amortization											28.6	103.4	41.2
Restructuring charges											3.3	16.3
Impairment of assets											0.0	7.5	0.0
Transaction costs											0.0	3.2	0.0
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property											(0.4)	0.0	3.5
Sale Leaseback Transaction, Current Period Gain Recognized											(6.5)	(22.9)	(3.3)
Costs and Expenses											39.2	193.9	177.5
Operating income (loss)											(34.8)	(61.1)	24.0
Interest Income (Expense), Net											(1.7)	2.8	6.0
Other expense (income), net											(2.3)	2.2	2.0
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax											97.7	(66.1)	16.0
Income tax expense (benefit)											34.8	(24.0)	5.8
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent											62.9	(42.1)	10.2
Disposal Group, Including Discontinued Operation, Other Assets, Current	0.0				1.5						0.0	1.5
Disposal Group, Including Discontinued Operation, Assets, Current	0.0				4.7						0.0	4.7
Property, plant and equipment, net	0.0				44.1						0.0	44.1
Intangible Assets, Net (Excluding Goodwill)	0.0				0.5						0.0	0.5
Disposal Group, Including Discontinued Operation, Assets, Noncurrent	0.0				44.6						0.0	44.6
Disposal Group, Including Discontinued Operation, Assets	0.0				49.3						0.0	49.3
Current portion of long-term debt	0.0				1.6						0.0	1.6
Accounts payable	0.0				5.0						0.0	5.0
Restructuring Reserve	4.7				15.4						4.7	15.4
Deferred Gain on Sale of Property	0.0				112.6						0.0	112.6
Disposal Group, Including Discontinued Operation, Other Liabilities, Current	0.7				7.4						0.7	7.4
Disposal Group, Including Discontinued Operation, Liabilities, Current	5.4				142.0						5.4	142.0
Long-term debt, less current portion	0.0				81.6						0.0	81.6
Disposal Group, Including Discontinued Operation, Liabilities, Noncurrent	0.0				102.7						0.0	102.7
Gain (Loss) on Disposition of Assets													3.5
Impairment of assets											0.0	7.5	0.0
Increase (Decrease) in Prepaid Rent											3.2	3.2	0.0
Payments for Restructuring											(14.5)	(2.4)	(0.3)
Capital expenditures											0.0	(6.5)	(16.0)
Repayment of debt											(0.3)	(23.5)	(0.6)
Operating lease expense											1.4	6.4	6.5
Continuing Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Long-term Debt, Current Maturities					1.1							1.1		1.1
Long-term Debt, Excluding Current Maturities					57.0							57.0		53.4
Depreciation and amortization											141.6	127.6	128.4
Income tax expense (benefit)											159.8	81.4	(8.3)
Other Liabilities, Noncurrent					7.5							7.5		10.9
Liabilities					65.6							65.6		$ 65.4
Capital expenditures											(283.6)	(175.8)	(180.9)
Wireless Towers [Member] | Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Deferred Gain on Sale of Property	$ 0.0				$ 13.1						0.0	13.1
Contract Termination [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Restructuring charges												13.1
Employee Severance [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Restructuring charges											3.3	1.0	9.0
Payments for Restructuring											(6.1)	(6.4)	(7.1)
Employee Severance [Member] | Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Restructuring charges												3.2
Lease Abandonment [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Restructuring charges											0.3	(1.4)	3.9
Payments for Restructuring											$ (1.3)	(2.6)	(3.3)
Lease Abandonment [Member] | Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Restructuring charges													$ 0.2
Senior Notes due 2020 [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Extinguishment of Debt, Amount												$ 22.7
Computer Software, Intangible Asset [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Property, Plant and Equipment, Useful Life										3 years
Property, Plant and Equipment [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Property, Plant and Equipment, Useful Life									30 months