XML 201 R34.htm IDEA: XBRL DOCUMENT v3.20.2
Convertible Notes Payable - Narrative (Details) - Convertible debt - 3.00% Convertible notes
1 Months Ended
Sep. 12, 2017
USD ($)
day
business_day
$ / shares
Sep. 30, 2020
USD ($)
Sep. 17, 2019
USD ($)
Aug. 14, 2017
USD ($)
Debt Instrument [Line Items]        
Aggregate principal amount $ 5,000,000.0     $ 300,000,000.0
Debt instrument stated rate 3.00%     3.00%
Debt issuance costs $ 9,400,000      
Debt instrument term 7 years      
Conversion ratio 0.0204891      
Initial conversion price (in dollars per share) | $ / shares $ 48.81      
Initial carrying amount   $ 208,902,000 $ 166,300,000  
Equity component   134,450,000 138,700,000  
Proceeds from the issuance of debt   $ 305,000,000 $ 305,000,000.0  
Debt discount, remaining discount amortization period 7 years      
Effective interest rate   13.04%    
Estimated fair value   $ 250,800,000    
Stock price trigger at greater than or equal to 130%        
Debt Instrument [Line Items]        
Consecutive or non-consecutive trading days 20 days      
Consecutive trading days | day 30      
Percentage of stock price trigger 130.00%      
Stock price trigger less than 98%        
Debt Instrument [Line Items]        
Consecutive trading days | day 5      
Percentage of stock price trigger 98.00%      
Trading days | business_day 5      
Stock price trigger at greater than or equal to 130%, on or after September 1, 2021        
Debt Instrument [Line Items]        
Consecutive or non-consecutive trading days 20 days      
Consecutive trading days | day 30      
Percentage of stock price trigger 130.00%      
Consecutive trading days, redemption notice period | day 5      
Additional Paid-In Capital        
Debt Instrument [Line Items]        
Debt issuance costs $ 4,300,000      
Convertible notes        
Debt Instrument [Line Items]        
Debt issuance costs $ 5,100,000