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Intangible Assets and Goodwill (Tables) | 12 Months Ended
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Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract] |
Intangible assets | Intangible assets, net of accumulated amortization, impairment charges and adjustments are summarized as follows:
|  |  | As of December 31, 2020 |  | As of December 31, 2019
(In millions) | Estimated Life |  | Cost |  | Accumulated Amortization |  | Net |  | Cost |  | Accumulated Amortization |  | Net
Completed technology | 4-28 years |  | $ | 7,394.3 |  |  | $ | (5,136.5) |  |  | $ | 2,257.8 |  |  | $ | 7,379.3 |  |  | $ | (4,881.4) |  |  | $ | 2,497.9 |
In-process research and development | Indefinite until commercialization |  | 762.5 |  |  | — |  |  | 762.5 |  |  | 965.5 |  |  | — |  |  | 965.5 |
Trademarks and trade names | Indefinite |  | 64.0 |  |  | — |  |  | 64.0 |  |  | 64.0 |  |  | — |  |  | 64.0 |
Total intangible assets |  |  | $ | 8,220.8 |  |  | $ | (5,136.5) |  |  | $ | 3,084.3 |  |  | $ | 8,408.8 |  |  | $ | (4,881.4) |  |  | $ | 3,527.4 |
Estimated future amortization of intangible assets | The estimated future amortization of finite-lived intangible assets for the next five years is expected to be as follows:
(In millions) |  | As of December 31, 2020
2021 |  | $ | 205.0 |
2022 |  | 215.0 |
2023 |  | 215.0 |
2024 |  | 225.0 |
2025 |  | 220.0 |
Summary of roll forward of the changes in goodwill | The following table provides a roll forward of the changes in our goodwill balance:
|  | As of December 31,
(In millions) |  | 2020 |  | 2019
Goodwill, beginning of year |  | $ | 5,757.8 |  |  | $ | 5,706.4 |
Increase to goodwill |  | — |  |  | 117.5 |
Elimination of goodwill allocated to Hillerød, Denmark manufacturing operations |  | — |  |  | (69.5) |
Other |  | 4.3 |  |  | 3.4 |
Goodwill, end of year |  | $ | 5,762.1 |  |  | $ | 5,757.8 |

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