Quarterly report pursuant to Section 13 or 15(d)

(2.0% Convertible Senior Notes Due 2025) (Details)

v3.20.2
(2.0% Convertible Senior Notes Due 2025) (Details) - 2.0% Convertible Senior Notes Due 2025 [Member]
$ / shares in Units, $ in Thousands, shares in Millions
9 Months Ended
Sep. 30, 2020
USD ($)
$ / shares
shares
Feb. 29, 2020
USD ($)
Debt Instrument [Line Items]    
Face amount $ 400,000 $ 400,000
Interest rate, stated percentage 2.00% 2.00%
Conversion ratio 0.0094469  
Conversion premium 50.00%  
Last reported sale price used to calculate conversion premium | $ / shares $ 70.57  
Maximum number of shares issuable upon conversion | shares 3.8  
Carrying amount of the equity component $ 33,900  
Unamortized debt discount balance $ 29,600  
Debt discount amortization period 4 years  
Effective interest rate 4.30%  
Redemption, Redeem For Cash [Member]    
Debt Instrument [Line Items]    
Redemption price, percentage 100.00%  
Debt Instrument, Redemption, Fundamental Change [Member]    
Debt Instrument [Line Items]    
Redemption price, percentage 100.00%