Fair Value Measurements - Summary of Carrying Amounts and Fair Values of Long-Term Borrowings (Details) - USD ($) $ in Millions |
Mar. 30, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Carrying Amount | $ 3,043.5 | $ 3,175.0 |
| Convertible notes | ||
| Carrying Amount | 1,089.9 | 1,080.1 |
| Fair Value | 1,749.0 | 1,596.7 |
| Long-term debt | ||
| Carrying Amount | 1,705.6 | 1,833.2 |
| Fair Value | $ 1,700.9 | $ 1,845.4 |