Leases Term

No definition available.

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- Definition

Minimum Percentage Of Estimated Economic Life Of Leased Assets To Be Classified Under Capital Lease"

+ References

No definition available.

+ Details

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- Definition

Minimum Percentage Of Fair Value Of Leased Assets As Net Present Value To Be Classified Under Capital Lease

+ References

No definition available.

+ Details

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- Definition

Receivables Due Term

+ References

No definition available.

+ Details

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

No definition available.

+ Details

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- Definition

Transaction Related Compensation

+ References

No definition available.

+ Details

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- Definition

The charge against earnings resulting from the aggregate write down of all assets from their carrying value to their fair value.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

+ References

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

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-Name Accounting Standards Codification

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-Paragraph 28

-Subparagraph (b)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-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

The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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- Definition

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.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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Significant Accounting Policies - Additional Information (Detail) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	3 Months Ended	8 Months Ended	1 Months Ended	3 Months Ended				2 Months Ended	3 Months Ended	2 Months Ended	3 Months Ended	1 Months Ended		3 Months Ended						0 Months Ended	3 Months Ended	0 Months Ended	3 Months Ended	0 Months Ended
	Mar. 31, 2014	Sep. 30, 2013	Jan. 23, 2013 Cincinnati Bell Inc. [Member]	Mar. 31, 2014 Minimum [Member]	Mar. 31, 2014 Minimum [Member] Trademarks and Customer Relationships [Member]	Mar. 31, 2014 Maximum [Member]	Mar. 31, 2014 Maximum [Member] Trademarks and Customer Relationships [Member]	Mar. 31, 2013 Successor [Member]	Mar. 31, 2014 Successor [Member]	Mar. 31, 2013 Successor [Member] CyrusOne L.P. [Member]	Mar. 31, 2014 Successor [Member] CyrusOne L.P. [Member]	Jan. 23, 2013 Predecessor [Member]	Jan. 23, 2013 Predecessor [Member] CyrusOne L.P. [Member]	Mar. 31, 2014 Building [Member] Minimum [Member]	Mar. 31, 2014 Building [Member] Maximum [Member]	Mar. 31, 2014 Building Improvements [Member] Minimum [Member]	Mar. 31, 2014 Building Improvements [Member] Maximum [Member]	Mar. 31, 2014 Equipment [Member] Minimum [Member]	Mar. 31, 2014 Equipment [Member] Maximum [Member]	Jan. 25, 2013 Restricted Stock [Member]	Mar. 31, 2014 Restricted Stock [Member]	Apr. 17, 2013 Performance Shares [Member]	Mar. 31, 2014 Performance Shares [Member]	Apr. 17, 2013 Performance Criteria [Member] Performance Shares [Member]	Apr. 17, 2013 Market Conditions [Member] Performance Shares [Member]
Summary Of Significant Accounting Policies [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period																				1	1
Receivables Due Term				30 days		120 days
Percentage of lease term	75.00%
Percentage of lease payment	90.00%
Impairments amount recognized	$ 0
Useful life of finite-lived intangible assets					8 years		15 years
Lease term of favorable leasehold interest which being amortized	56 years
Transaction-related compensation			20,000,000					0	0	0	0	20,000,000	20,000,000
Asset impairments								0				0
Property, Plant and Equipment, Useful Life		25 years												9 years	48 years	3 years	25 years	3 years	5 years
Impairment of Real Estate	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period																				3 years	3 years	3 years	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value																				$ 19.00
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage																								50.00%	50.00%