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Description of the Business and Summary of Significant Accounting Policies - Property and Equipment, Net (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Property, Plant and Equipment [Line Items] |  |  |
Depreciation | $ 158.6 | $ 170.7 | $ 173.8
Minimum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property and equipment, useful life | 3 years |  |
Minimum | Infrastructure Equipment |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property and equipment, useful life | 3 years |  |
Minimum | Buildings |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property and equipment, useful life | 20 years |  |
Minimum | Datacenter and other computer equipment |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property and equipment, useful life | 3 years |  |
Minimum | Office equipment and other |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property and equipment, useful life | 3 years |  |
Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property and equipment, useful life | 7 years |  |
Maximum | Infrastructure Equipment |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property and equipment, useful life | 4 years |  |
Maximum | Buildings |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property and equipment, useful life | 30 years |  |
Maximum | Datacenter and other computer equipment |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property and equipment, useful life | 5 years |  |
Maximum | Office equipment and other |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property and equipment, useful life | 7 years |  |
Change in Accounting Method Accounted for as Change in Estimate |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Depreciation | $ (16.1) |  |

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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
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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. + Details
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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. + Details
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