Debt (Lease Narrative) (Details) $ in Millions	9 Months Ended
Sep. 30, 2017 USD ($) agreement facility	Dec. 31, 2016 USD ($)
Capital Leased Assets [Line Items]
Lease financing obligations	$ 18.8	$ 20.6
Carpathia Hosting, Inc.
Capital Leased Assets [Line Items]
Capital lease, lease financing obligations and mortgage notes payable	10.0
Capital lease and lease financing obligations assumed	$ 7.1
Number of lease agreements \| agreement	2
Lease financing obligations	$ 18.8
The number of data centers with lease agreements and lease financing agreements \| facility	1
Outstanding financing agreement	$ 1.0
Deferred gain of lease financing obligations	$ 1.4
Lease financing expiration date	Feb. 01, 2019
Carpathia Hosting, Inc. \| Sale-Leaseback Transaction [Member]
Capital Leased Assets [Line Items]
Capital lease and lease financing obligations assumed	$ 17.8
Outstanding financing agreement	16.4
Carpathia Hosting, Inc. \| Tenant Improvement Allowance [Member]
Capital Leased Assets [Line Items]
Lease financing obligations	$ 4.8
Minimum \| Carpathia Hosting, Inc.
Capital Leased Assets [Line Items]
Lease expiration year	2018
Monthly lease payment	$ 0.2
Maximum \| Carpathia Hosting, Inc.
Capital Leased Assets [Line Items]
Lease expiration year	2019
Monthly lease payment	$ 0.5
Lease financing monthly principal and interest payment	$ 0.1

Lease expiration year

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- Definition

Lease financing obligations

+ References

No definition available.

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- Definition

Monthly lease payment

+ References

No definition available.

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- Definition

The number of data centers with lease agreements and lease financing agreements.

+ References

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- Definition

Number of lease agreements

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No definition available.

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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- Definition

The increase during the period in capital lease obligations due to entering into new capital leases.

+ References

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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

The liability due as of the balance sheet date for leasebacks accounted for using the deposit method.

+ References

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-Name Accounting Standards Codification
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-SubTopic 40
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- Definition

Amount of cash inflow after closing and debt issuance costs received by a seller-lessee in a sale-leaseback recognized in financing activities.

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

Other amounts the seller-lessee is required to pay under the terms of the transaction involving the sale of property to another party and lease of the property back to the seller, including reimbursements for such items, as utilities, taxes, insurance and common area maintenance.

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