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Goodwill and Other Intangible Assets - Goodwill Rollforward (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | Dec. 31, 2016 | Dec. 31, 2015
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |  |  |
Liabilities | $ 299.9 |  | $ 299.9 |  | $ 2,804.2 |
Goodwill [Roll Forward] |  |  |  |  |  |
Goodwill, beginning balance | 25.9 | $ 18.3 | 25.9 | $ 18.6 |  |
Intangible assets, net (including Goodwill), beginning balance | 40.3 | 41.6 | 45.2 | 45.5 |  |
Add: Amounts held for sale at beginning of the period |  |  |  |  | 0.0 | $ 0.4
Acquisition of businesses | 0.0 | 1.1 | 0.0 |  |  |
Wobi write off |  |  |  | (0.3) |  |
Wobi write off |  |  |  | (2.8) |  |
Acquisitions of goodwill |  | 7.6 |  | 7.6 |  |
Amortization, including foreign currency translation | (2.5) | (2.6) | (7.4) | (8.0) |  |
Goodwill, ending balance | 25.9 | 25.9 | 25.9 | 25.9 |  |
Intangible assets, net (including Goodwill), ending balance | 37.8 | 47.7 | 37.8 | 47.7 |  |
Assets | 3,637.1 |  | 3,637.1 |  | 6,520.2 |
Other Intangible Assets |  |  |  |  |  |
Goodwill [Roll Forward] |  |  |  |  |  |
Other intangible assets, beginning balance | 14.4 | 23.3 | 19.3 | 26.9 |  |
Add: Amounts held for sale at beginning of the period |  |  |  |  | $ 0.0 | $ 0.4
Acquisition of businesses |  |  |  | 5.0 |  |
Wobi write off |  |  |  | (2.5) |  |
Amortization, including foreign currency translation | (2.5) | (2.6) | (7.4) | (8.0) |  |
Other intangible assets, ending balance | $ 11.9 | 21.8 | $ 11.9 | 21.8 |  |
Intangible Asset and Goodwill |  |  |  |  |  |
Goodwill [Roll Forward] |  |  |  |  |  |
Acquisition of businesses |  | $ 8.7 |  | $ 12.6 |  |

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- Definition Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph ((a)(1),(b)) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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