Annual report pursuant to Section 13 and 15(d)

LONG-TERM DEBT (Schedule of Debt Interest Expense) (Details)

v3.20.4
LONG-TERM DEBT (Schedule of Debt Interest Expense) (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
2.5% Convertible Senior Notes Due 2019 and 2023 [Member]      
Debt Instrument [Line Items]      
Contractual interest coupon   $ 14,015 $ 12,894
Amortization of debt discount (premium)   12,599 10,746
Amortization of debt issuance costs   2,134 1,940
Total interest cost recognized on the notes   $ 28,748 $ 25,580
2.5% Convertible Senior Notes Due 2023 and 2.0% Convertible Senior Notes Due 2025 [Member]      
Debt Instrument [Line Items]      
Contractual interest coupon $ 21,011    
Amortization of debt discount (premium) 19,260    
Amortization of debt issuance costs 3,230    
Total interest cost recognized on the notes $ 43,501