Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Narrative (Details)

v3.21.2
Fair Value Measurements - Narrative (Details) - USD ($)
$ in Millions
9 Months Ended
Sep. 30, 2021
Dec. 31, 2020
Equity Method Investments    
Fair Value Measurements    
Investment in private company $ 1.5  
Level II | Equity Method Investments    
Fair Value Measurements    
Price adjustment 0.8  
Convertible Notes due 2023    
Fair Value Measurements    
Debt instrument, fair value disclosure 434.7 $ 460.8
Convertible Notes due 2023 | Carrying Value    
Fair Value Measurements    
Convertible notes 341.5 316.6
Convertible Notes due 2025    
Fair Value Measurements    
Debt instrument, fair value disclosure 523.0 540.8
Convertible Notes due 2025 | Carrying Value    
Fair Value Measurements    
Convertible notes $ 506.1 $ 439.9