v3.19.3
Fair Value Measurements - Additional Information (Details)
$ in Thousands
9 Months Ended
Sep. 30, 2019
USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Fair value assets transferred from level 1 to level 2 $ 0
Fair value assets transferred from level 2 to level 1 0
Fair value liabilities transferred from level 1 to level 2 0
Fair value liabilities transferred from level 2 to level 1 0
Other-than-temporary impaired investments 0
Level 2 Securities  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Convertible notes $ 1,300,000