v3.10.0.1
STOCKHOLDERS' EQUITY - equity statements (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Sep. 30, 2018
Sep. 30, 2017
Increase (Decrease) in Stockholders' Equity                
Balance at the beginning of the period $ 1,969.9 $ 2,084.8 $ 2,112.4 $ 2,476.6 $ 2,600.6 $ 2,009.6 $ 2,112.4 $ 2,009.6
Balance (in shares)     75,826,927       75,826,927  
Cumulative Effect of New Accounting Principle in Period of Adoption     $ (31.8)          
Net earnings (loss) (100.4) 22.2 17.7 (42.7) (176.5) 8.4 $ (60.5) (210.8)
Other comprehensive income (loss) (7.5) (107.0) 10.5 33.7 76.5 (1.9) (103.9) 108.3
RSUs surrendered to pay for payroll taxes     (1.8)     (6.5)    
Net proceeds from equity offering         (0.9) 617.7   616.8
Reclassification from temporary equity   0.1 0.3   0.3      
Stock-based compensation 4.2 4.0 2.8 (0.3) 3.0 (0.4)    
Purchase shares for treasury   (8.2)   (16.5)        
Common stock repurchase and cancellation (422.9)           (422.9)  
Balance at the end of the period 1,254.5 1,969.9 2,084.8 2,424.4 2,476.6 2,600.6 1,254.5 2,424.4
Reversed dividend accrual                
Increase (Decrease) in Stockholders' Equity                
Dividends declared     0.7          
Additional Paid-in Capital                
Increase (Decrease) in Stockholders' Equity                
Balance at the beginning of the period 2,247.0 2,242.9 2,241.6 2,240.3 2,237.9 1,627.3 2,241.6 1,627.3
RSUs surrendered to pay for payroll taxes     (1.8)     (6.5)    
Net proceeds from equity offering         (0.9) 617.5    
Reclassification from temporary equity   0.1 0.3   0.3      
Stock-based compensation 4.2 4.0 2.8 (0.3) 3.0 (0.4)    
Common stock repurchase and cancellation (256.7)              
Balance at the end of the period 1,994.5 2,247.0 2,242.9 2,240.0 2,240.3 2,237.9 1,994.5 2,240.0
Treasury Stock                
Increase (Decrease) in Stockholders' Equity                
Balance at the beginning of the period $ (56.4) $ (48.2) $ (48.2) $ (0.7) $ (0.7) $ (0.7) $ (48.2) $ (0.7)
Balance (in shares) 3,732,625 3,232,625 3,232,625 36,769 36,769 36,769 3,232,625 36,769
Purchase shares for treasury   $ (8.2)   $ (16.5)        
Purchase shares for treasury, shares   500,000   1,068,300        
Balance at the end of the period $ (56.4) $ (56.4) $ (48.2) $ (17.2) $ (0.7) $ (0.7) $ (56.4) $ (17.2)
Balance (in shares) 3,732,625 3,732,625 3,232,625 1,105,069 36,769 36,769 3,732,625 1,105,069
Accumulated Other Comprehensive Income (Loss)                
Increase (Decrease) in Stockholders' Equity                
Balance at the beginning of the period $ 33.5 $ 140.5 $ 125.6 $ 72.1 $ (4.4) $ (2.5) $ 125.6 $ (2.5)
Cumulative Effect of New Accounting Principle in Period of Adoption     4.4          
Other comprehensive income (loss) (7.5) (107.0) 10.5 33.7 76.5 (1.9) (104.0)  
Balance at the end of the period 26.0 33.5 140.5 105.8 72.1 (4.4) 26.0 105.8
Accumulated Earnings (Deficit)                
Increase (Decrease) in Stockholders' Equity                
Balance at the beginning of the period (255.5) (251.7) (207.9) 163.6 366.5 384.4 (207.9) 384.4
Cumulative Effect of New Accounting Principle in Period of Adoption     (36.2)          
Net earnings (loss) (100.4) 22.2 17.7 (42.7) (176.5) 8.4    
Common stock repurchase and cancellation (165.9)              
Balance at the end of the period $ (710.6) (255.5) (251.7) 94.5 163.6 366.5 $ (710.6) 94.5
Accumulated Earnings (Deficit) | Reversed dividend accrual                
Increase (Decrease) in Stockholders' Equity                
Dividends declared     $ 0.7          
Class A common stock                
Increase (Decrease) in Stockholders' Equity                
Balance (in shares)     51,814,304       51,814,304  
Balance (in shares) 51,705,469           51,705,469  
Class A common stock | Dividend declared                
Increase (Decrease) in Stockholders' Equity                
Dividends declared $ (10.6) (10.8) $ (10.8) (11.2) (11.2) (11.1)    
Class A common stock | Special dividend declared                
Increase (Decrease) in Stockholders' Equity                
Dividends declared (82.7)              
Class A common stock | Common Stock                
Increase (Decrease) in Stockholders' Equity                
Balance at the beginning of the period $ 0.5 $ 0.5 $ 0.5 $ 0.5 $ 0.5 $ 0.3 $ 0.5 $ 0.3
Balance (in shares) 55,401,325 55,391,415 55,010,160 55,002,524 54,974,532 34,236,561 55,010,160 34,236,561
RSUs surrendered to pay for payroll taxes (shares)     326,005   795 393,413    
Net proceeds from equity offering           $ 0.2    
Additional offering (in shares)           20,330,874    
Reclassification from temporary equity (in shares)   9,910 27,195   27,197      
Stock based compensation (in shares)     28,055     13,684    
Balance at the end of the period $ 0.5 $ 0.5 $ 0.5 $ 0.5 $ 0.5 $ 0.5 $ 0.5 $ 0.5
Balance (in shares) 55,401,325 55,401,325 55,391,415 55,002,524 55,002,524 54,974,532 55,401,325 55,002,524
Class A common stock | Accumulated Earnings (Deficit) | Dividend declared                
Increase (Decrease) in Stockholders' Equity                
Dividends declared $ (10.6) $ (10.8) $ (10.8) $ (11.2) $ (11.2) $ (11.1)    
Class A common stock | Accumulated Earnings (Deficit) | Special dividend declared                
Increase (Decrease) in Stockholders' Equity                
Dividends declared $ (82.7)              
Class B common stock                
Increase (Decrease) in Stockholders' Equity                
Balance (in shares) 51,769,784           51,769,784  
Class B common stock | Dividend declared                
Increase (Decrease) in Stockholders' Equity                
Dividends declared $ (15.3) (15.2) (15.2) (15.2) (15.2) (15.2)    
Class B common stock | Special dividend declared                
Increase (Decrease) in Stockholders' Equity                
Dividends declared (80.2)              
Class B common stock | Common Stock                
Increase (Decrease) in Stockholders' Equity                
Balance at the beginning of the period $ 0.8 $ 0.8 $ 0.8 $ 0.8 $ 0.8 $ 0.8 $ 0.8 $ 0.8
Balance (in shares) 75,826,927 75,826,927 75,826,927 75,826,927 75,826,927 75,826,927 75,826,927 75,826,927
Common stock repurchase and cancellation $ (0.3)              
Common stock repurchased and cancellation (in shares) (24,057,143)              
Balance at the end of the period $ 0.5 $ 0.8 $ 0.8 $ 0.8 $ 0.8 $ 0.8 $ 0.5 $ 0.8
Balance (in shares) 51,769,784 75,826,927 75,826,927 75,826,927 75,826,927 75,826,927 51,769,784 75,826,927
Class B common stock | Accumulated Earnings (Deficit) | Dividend declared                
Increase (Decrease) in Stockholders' Equity                
Dividends declared $ (15.3) $ (15.2) $ (15.2) $ (15.2) $ (15.2) $ (15.2)    
Class B common stock | Accumulated Earnings (Deficit) | Special dividend declared                
Increase (Decrease) in Stockholders' Equity                
Dividends declared $ (80.2)