Other Financial Information - Accrued Expenses and Other Liabilities (Details) - USD ($) $ in Millions |
Sep. 30, 2020 |
Dec. 31, 2019 |
Sep. 30, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|---|---|---|---|
| Organization, Consolidation and Presentation of Financial Statements [Abstract] | ||||||
| Deferred revenue | $ 189.8 | $ 160.9 | $ 170.5 | |||
| Accrued payroll and other employee compensation | 128.9 | 145.4 | ||||
| Litigation reserve (see note 17) | 96.6 | 92.9 | 60.0 | |||
| Contract liabilities (see note 3) | 48.3 | 39.8 | ||||
| Operating lease liabilities | 38.2 | 35.0 | ||||
| Product warranty | 33.1 | 43.2 | 44.9 | |||
| Restructuring (see note 4) | 77.3 | 22.2 | $ 18.1 | 25.8 | $ 28.3 | $ 15.6 |
| Other | 264.6 | 328.3 | ||||
| Accrued expenses and other liabilities | $ 876.8 | $ 867.7 | $ 804.3 |