Quarterly report pursuant to Section 13 or 15(d)

LONG-TERM DEBT (2.5% Convertible Senior Notes Due 2023) (Details)

v3.10.0.1
LONG-TERM DEBT (2.5% Convertible Senior Notes Due 2023) (Details) - 2.5% Convertible Senior Notes Due 2023 [Member]
$ / shares in Units, shares in Millions, $ in Millions
9 Months Ended
Sep. 30, 2018
USD ($)
$ / shares
shares
Mar. 31, 2018
USD ($)
Debt Instrument [Line Items]    
Face Amount $ 550.0 $ 550.0
Interest rate, stated percentage 2.50% 2.50%
Conversion ratio 0.0147005  
Conversion premium 54.40%  
Last reported sale price used to calculate conversion premium ($ / share) | $ / shares $ 44.05  
Maximum number of shares issuable upon conversion (shares) | shares 8.1  
Carrying amount of the equity component $ 64.0  
Debt discount amortization period 4 years  
Effective interest rate 5.70%  
Redemption, Defined Changes of Control [Member]    
Debt Instrument [Line Items]    
Redemption price, percentage 100.00%