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Goodwill and Other Intangible Assets - Schedule of Goodwill and Other Intangible Assets Footnotes (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2019 | Dec. 31, 2018
Goodwill |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Foreign currency translation | $ (1.2) | $ 0.0 |
NSM Holding Co LLC | Other Intangible Assets |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Foreign currency translation |  | $ 0.4 | $ (0.7)
NSM Holding Co LLC | Goodwill |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Foreign currency translation | $ (0.1) |  | (2.2)
Buzzmove | Goodwill |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Foreign currency translation |  |  | $ (0.3)

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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 Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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