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The increase in depreciation expense associated with a reduction in the useful lives of property, plant and equipment.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Details

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The number of operating partnership units of CyrusOne LP sold during the period.

No definition available.

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Data Type:	xbrli:sharesItemType
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Period Type:	duration

The number of partnership units of CyrusOne LP, the operating partnership, owned by the Company. These partnership units are exchangeable into shares of common stock of CyrusOne Inc. on a one-for-one basis.

No definition available.

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Data Type:	xbrli:sharesItemType
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The Company's ownership interest, in shares, in the common stock of CyrusOne Inc., the publicly-traded real estate investment trust entity, following the completion of the initial public offering on January 24, 2013.

No definition available.

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Data Type:	xbrli:sharesItemType
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Period Type:	instant

The Company's ownership interest in CyrusOne Inc., the publicly-traded real estate investment trust entity, following the completion of the initial public offering on January 24, 2013.

No definition available.

Name:	cbb_InvestmentownedinEquityMethodInvesteePercentageCommonStock
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Data Type:	num:percentItemType
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Period Type:	instant

The company's percentage ownership interest in CyrusOne LP, the operating partnership, after the initial public offering of CyrusOne Inc. on January 24, 2013.

No definition available.

Name:	cbb_InvestmentownedinEquityMethodInvesteePercentagePartnershipUnits
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Data Type:	num:percentItemType
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The per-unit sales price received by the Company for each operating partnership unit of CyrusOne LP sold during the period.

No definition available.

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Data Type:	num:perShareItemType
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The Company's total combined direct and indirect owership interests in CyrusOne Inc., the REIT entity, and CyrusOne LP, the operating partnership.

No definition available.

Name:	cbb_TotalownershipinterestsinEquityMethodInvesteePercentage
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Data Type:	num:percentItemType
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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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Cash dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporations that are returns of capital. Excludes dividends or distributions from equity method investments classified as operating activities.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

No definition available.

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The portion of the deferred gain that was recognized in the current period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 35

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35688829&loc=d3e50609-112754

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 45

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=37586315&loc=d3e32123-109318