Restructuring Charges (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Restructuring Reserve [Roll Forward]
Beginning balance	$ 13.5	$ 24.0	$ 20.3
Charges	13.7	3.4	12.2
Utilizations	(11.4)	(13.9)	(8.5)
Ending balance	15.8	13.5	24.0
Restructuring liabilities included in other current liabilities	7.8	5.8
Restructuring liabilities included in other noncurrent liabilities	8.0	7.7
Wireline [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	8.6	15.1	12.8
Charges	9.1	3.5	7.7
Utilizations	(7.2)	(10.0)	(5.4)
Ending balance	10.5	8.6	15.1
Wireless [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	1.6	0.7	1.0
Charges	0.2	1.6	0
Utilizations	(0.3)	(0.7)	(0.3)
Ending balance	1.5	1.6	0.7
IT Services and Hardware [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.5	2.5	1.3
Charges	0.7	(1.2)	1.9
Utilizations	(0.4)	(0.8)	(0.7)
Ending balance	0.8	0.5	2.5
Data Center Colocation [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0	0	1.4
Charges	0	0.5	0
Utilizations	0	(0.5)	(1.4)
Ending balance	0	0	0
Corporate Segment [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	2.8	5.7	3.8
Charges	3.7	(1.0)	2.6
Utilizations	(3.5)	(1.9)	(0.7)
Ending balance	3.0	2.8	5.7
Employee Severance [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	7.8	14.2	11.7
Charges	9.0	2.5	8.0
Utilizations	(7.1)	(8.9)	(5.5)
Ending balance	9.7	7.8	14.2
Lease Abandonment [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	5.5	8.1	7.2
Charges	4.1	0.9	2.5
Utilizations	(3.6)	(3.5)	(1.6)
Ending balance	6.0	5.5	8.1
Other Restructuring [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.2	1.7	1.4
Charges	0.6	0	1.7
Utilizations	(0.7)	(1.5)	(1.4)
Ending balance	$ 0.1	$ 0.2	$ 1.7