Annual report pursuant to Section 13 and 15(d)

FAIR VALUE MEASUREMENTS (Narrative) (Details)

v3.3.1.900
FAIR VALUE MEASUREMENTS (Narrative) (Details) - USD ($)
$ in Millions
Dec. 31, 2015
Dec. 31, 2014
May. 31, 2014
Aug. 31, 2013
7% Senior Notes Due 2020 [Member]        
Debt Fair Value [Line Items]        
Interest rate, stated percentage 7.00%     7.00%
5.375% Senior Notes due 2022 [Member]        
Debt Fair Value [Line Items]        
Interest rate, stated percentage 5.375%   5.375%  
2.5% Convertible Senior Notes Due 2019 [Member]        
Debt Fair Value [Line Items]        
Interest rate, stated percentage 2.50%   2.50%  
Fixed Rate Debt With Noncontrolling Interest Partner [Member]        
Estimate of fair value not practicable [Abstract]        
Face amount of debt $ 26.9 $ 30.0    
Level 2 [Member] | 7% Senior Notes Due 2020 [Member]        
Debt Fair Value [Line Items]        
Interest rate, stated percentage 7.00% 7.00%    
Estimated fair values of senior notes $ 443.1 $ 451.3    
Level 2 [Member] | 5.375% Senior Notes due 2022 [Member]        
Debt Fair Value [Line Items]        
Interest rate, stated percentage 5.375% 5.375%    
Estimated fair values of senior notes $ 249.4 $ 250.3    
Level 2 [Member] | 2.5% Convertible Senior Notes Due 2019 [Member]        
Debt Fair Value [Line Items]        
Interest rate, stated percentage 2.50% 2.50%    
Estimated fair values of convertible senior notes $ 280.2 $ 296.3