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Intangible Assets and Goodwill (Tables) | 12 Months Ended
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Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract] |
Intangible assets |
|  |  | As of December 31, 2015 |  | As of December 31, 2014
(In millions) | Estimated Life |  | Cost |  | Accumulated Amortization |  | Net |  | Cost |  | Accumulated Amortization |  | Net
Out-licensed patents | 13-23 years |  | $ | 543.3 |  |  | $ | (506.0 | ) |  | $ | 37.3 |  |  | $ | 543.3 |  |  | $ | (481.7 | ) |  | $ | 61.6 |
Developed technology | 15-23 years |  | 3,005.3 |  |  | (2,552.9 | ) |  | 452.4 |  |  | 3,005.3 |  |  | (2,396.8 | ) |  | 608.5 |
In-process research and development | Indefinite until commercialization |  | 730.5 |  |  | — |  |  | 730.5 |  |  | 314.1 |  |  | — |  |  | 314.1 |
Trademarks and tradenames | Indefinite |  | 64.0 |  |  | — |  |  | 64.0 |  |  | 64.0 |  |  | — |  |  | 64.0 |
Acquired and in-licensed rights and patents | 6-18 years |  | 3,303.2 |  |  | (502.3 | ) |  | 2,800.9 |  |  | 3,280.4 |  |  | (300.1 | ) |  | 2,980.3 |
Total intangible assets |  |  | $ | 7,646.3 |  |  | $ | (3,561.2 | ) |  | $ | 4,085.1 |  |  | $ | 7,207.1 |  |  | $ | (3,178.6 | ) |  | $ | 4,028.5 |
Estimated future amortization of intangible assets |
(In millions) | As of December 31, 2015
2016 | $ | 346.4 |
2017 | 318.6 |
2018 | 291.0 |
2019 | 275.1 |
2020 | 269.1 |
Total | $ | 1,500.2 |
Summary of roll forward of the changes in goodwill |
| As of December 31,
(In millions) | 2015 |  | 2014
Goodwill, beginning of year | $ | 1,760.2 |  |  | $ | 1,232.9 |
Increase to goodwill | 908.1 |  |  | 527.3 |
Other | (4.5 | ) |  | — |
Goodwill, end of year | $ | 2,663.8 |  |  | $ | 1,760.2 |

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- Definition Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267 + Details
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- Definition Tabular disclosure of the amount of amortization expense expected to be recorded in succeeding fiscal years for finite-lived intangible assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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