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Restructuring Restructuring (Details Textual) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Dec. 31, 2015 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  | $ 0.9 | $ 33.1 | $ 93.4
2017 Restructuring Charges [Member] |  |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |
Total non-recurring operation and capital expenditures | $ 170.0 |  |  |  |  |  |  |
Redirection of resources | $ 400.0 |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  | 19.4 |  |
2016 Restructuring Charges |  |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  | 17.7 |
2015 Restructuring Charges |  |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  | 8.0 | 93.4
Restructuring and related cost, expected percentage of positions eliminated |  |  |  |  | 11.00% |  |  |
Previously accrued incentive compensation |  |  |  |  | $ 120.0 |  |  | 120.0
Adjustments to previous estimates, net |  |  |  |  | 15.9 |  | (2.3) |
Total restructuring charges expected |  |  |  |  | $ 102.0 |  |  | $ 102.0
Cambridge, MA |  |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |
Accelerated depreciation |  | $ 14.0 | $ 15.7 | $ 15.8 |  |  | 45.5 |
Cambridge, MA | 2016 Restructuring Charges |  |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  | $ 7.4 |
Selling, general and administrative | 2017 Restructuring Charges [Member] |  |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  | 18.5 |  |
Restructuring charges | 2017 Restructuring Charges [Member] |  |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  | $ 0.9 |  |

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