Business Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Segment Reporting Information [Line Items]
Revenue	$ 368.2	$ 368.8	$ 1,099.2	$ 1,097.1
Intersegment Revenue	8.6	8.0	26.3	24.4
Operating Income (Loss)	66.0	86.3	212.2	250.3
Expenditures for long-lived assets	75.5	74.5	242.9	167.0
Depreciation and amortization	55.4	49.1	160.2	146.3
Assets	2,752.3		2,752.3		2,714.7
Wireline [Member]
Segment Reporting Information [Line Items]
Revenue	182.3	182.7	548.4	551.8
Intersegment Revenue	4.8	5.8	14.5	17.4
Operating Income (Loss)	50.9	65.2	162.8	180.2
Expenditures for long-lived assets	27.8	27.1	77.5	75.2
Depreciation and amortization	26.6	25.6	78.9	76.1
Assets	721.0		721.0		713.6
Corporate Elimination [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)	(12.5)	(5.8)	(23.8)	(17.8)
Depreciation and amortization	0	0.1	0.1	0.3
Assets	620.6		620.6		705.3
Wireless [Member]
Segment Reporting Information [Line Items]
Revenue	59.5	68.1	185.0	209.2
Intersegment Revenue	0.5	0.6	1.7	1.7
Operating Income (Loss)	12.6	11.6	43.5	43.1
Expenditures for long-lived assets	4.2	4.9	12.4	10.6
Depreciation and amortization	8.1	8.0	24.0	25.1
Assets	277.5		277.5		295.2
Data Center Colocation [Member]
Segment Reporting Information [Line Items]
Number of Data Centers	23		23
Revenue	56.7	47.1	163.3	135.6
Intersegment Revenue	1.5	0.5	4.7	1.6
Operating Income (Loss)	11.2	11.3	22.5	36.1
Expenditures for long-lived assets	41.6	41.0	146.4	77.2
Depreciation and amortization	18.3	13.2	50.9	38.2
Assets	1,089.0		1,089.0		964.0
IT Services and Hardware [Member]
Segment Reporting Information [Line Items]
Revenue	78.3	78.9	228.8	224.9
Intersegment Revenue	1.8	1.1	5.4	3.7
Operating Income (Loss)	3.8	4.0	7.2	8.7
Expenditures for long-lived assets	1.9	1.5	6.6	4.0
Depreciation and amortization	2.4	2.2	6.3	6.6
Assets	44.2		44.2		36.6
Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Revenue	$ (8.6)	$ (8.0)	$ (26.3)	$ (24.4)

Number of Data Centers

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- Definition

Total expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 28

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 7

-Section 03

-Paragraph 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Section S99

-Name Accounting Standards Codification

-Publisher FASB

-Paragraph 1

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

-Publisher FASB

-Name Statement of Financial Accounting Concepts (CON)

-Number 6

-Paragraph 25

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.18)

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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.

+ 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.

+ References

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- Definition

Amount of revenue from transactions with other operating segments of the same entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 27

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

-Paragraph 1

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

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