SUPPLEMENTAL GUARANTOR FINANCIAL INFORMATION (Balance Sheet)(Details) - USD ($)
$ in Millions
Jun. 30, 2017
Dec. 31, 2016
Jun. 30, 2016
Dec. 31, 2015
Supplemental Guarantor Financial Information Balance Sheets [Line Items]        
Cash and cash equivalents $ 184.5 $ 184.5 $ 66.6 $ 392.0
Receivables, net 782.2 675.0 790.5  
Intercompany receivables 0.0 0.0 0.0  
Income taxes receivable 20.9 25.5 45.8  
Inventories 666.2 630.4 636.2  
Other Assets, Current 37.2 30.8 23.8  
Total current assets 1,691.0 1,546.2 1,562.9  
Property, Plant and Equipment, Net 3,627.4 3,704.9 3,793.3  
Investment in subsidiaries 0.0 0.0 0.0  
Deferred income taxes 125.2 119.5 107.0  
Other Assets, Noncurrent 625.6 644.4 588.6  
Long-term receivables—affiliates 0.0 0.0 0.0  
Intangible Assets, Net 605.6 629.6 671.2  
Goodwill 2,119.5 2,118.0 2,186.3 2,174.1
Total assets 8,794.3 8,762.6 8,909.3  
Current installments of long-term debt 81.7 80.5 80.3  
Accounts payable 656.1 570.8 536.4  
Intercompany payables 0.0 0.0 0.0  
Income taxes payable 7.1 7.5 8.2  
Accrued Liabilities, Current 261.5 263.8 293.6  
Total current liabilities 1,006.4 922.6 918.5  
Long-term Debt, Excluding Current Maturities 3,518.9 3,537.1 3,615.5  
Accrued pension liability 625.6 638.1 616.7  
Deferred income taxes 1,037.6 1,032.5 1,079.3  
Long-term payables—affiliates 0.0 0.0 0.0  
Other Liabilities, Noncurrent 347.2 359.3 348.3  
Total liabilities 6,535.7 6,489.6 6,578.3  
Commitments and contingencies  
Common Stock, Value, Issued 166.3 165.4 165.2  
Additional Paid in Capital, Common Stock 2,262.7 2,243.8 2,240.3  
Accumulated other comprehensive loss (485.4) (510.0) (479.3) (492.5)
Retained Earnings (Accumulated Deficit) 315.0 373.8 404.8  
Total shareholders' equity 2,258.6 2,273.0 2,331.0 2,418.8
Total liabilities and shareholders' equity 8,794.3 8,762.6 8,909.3  
Parent Guarantor        
Supplemental Guarantor Financial Information Balance Sheets [Line Items]        
Cash and cash equivalents 28.9 25.2 23.2 119.4
Receivables, net 101.7 88.3 98.2  
Intercompany receivables 0.0 0.0 0.0  
Income taxes receivable 18.8 19.0 35.1  
Inventories 178.2 167.7 175.2  
Other Assets, Current 183.1 164.7 146.1  
Total current assets 510.7 464.9 477.8  
Property, Plant and Equipment, Net 509.1 510.1 494.7  
Investment in subsidiaries 6,082.7 6,035.2 5,957.3  
Deferred income taxes 151.8 133.5 166.2  
Other Assets, Noncurrent 46.9 48.1 40.4  
Long-term receivables—affiliates 0.0 0.0 0.0  
Intangible Assets, Net 0.4 0.4 0.5  
Goodwill 0.0 0.0 0.0  
Total assets 7,301.6 7,192.2 7,136.9  
Current installments of long-term debt 0.8 0.6 0.6  
Accounts payable 58.0 45.3 59.8  
Intercompany payables 2,055.8 1,882.8 1,734.4  
Income taxes payable 0.0 0.0 0.6  
Accrued Liabilities, Current 116.1 124.9 133.4  
Total current liabilities 2,230.7 2,053.6 1,928.8  
Long-term Debt, Excluding Current Maturities 822.3 913.9 1,158.3  
Accrued pension liability 421.7 453.7 164.1  
Deferred income taxes 0.0 0.0 0.0  
Long-term payables—affiliates 1,284.4 1,209.1 1,277.3  
Other Liabilities, Noncurrent 283.9 288.9 277.4  
Total liabilities 5,043.0 4,919.2 4,805.9  
Common Stock, Value, Issued 166.3 165.4 165.2  
Additional Paid in Capital, Common Stock 2,262.7 2,243.8 2,240.3  
Accumulated other comprehensive loss (485.4) (510.0) (479.3)  
Retained Earnings (Accumulated Deficit) 315.0 373.8 404.8  
Total shareholders' equity 2,258.6 2,273.0 2,331.0  
Total liabilities and shareholders' equity 7,301.6 7,192.2 7,136.9  
Issuer        
Supplemental Guarantor Financial Information Balance Sheets [Line Items]        
Cash and cash equivalents 0.0 0.0 0.0 0.0
Receivables, net 0.0 0.0 0.0  
Intercompany receivables 2.9 0.0 22.3  
Income taxes receivable 0.0 0.0 0.0  
Inventories 0.0 0.0 0.0  
Other Assets, Current 0.0 3.4 0.0  
Total current assets 2.9 3.4 22.3  
Property, Plant and Equipment, Net 0.0 0.0 0.0  
Investment in subsidiaries 3,774.0 3,734.7 3,655.0  
Deferred income taxes 0.0 0.0 0.0  
Other Assets, Noncurrent 0.0 0.0 0.0  
Long-term receivables—affiliates 2,204.3 2,194.2 2,262.4  
Intangible Assets, Net 5.7 5.7 5.7  
Goodwill 966.3 966.3 994.2  
Total assets 6,953.2 6,904.3 6,939.6  
Current installments of long-term debt 68.8 67.5 67.5  
Accounts payable 0.0 0.0 0.0  
Intercompany payables 0.0 29.5 0.0  
Income taxes payable 0.0 0.0 0.0  
Accrued Liabilities, Current 0.0 0.0 0.0  
Total current liabilities 68.8 97.0 67.5  
Long-term Debt, Excluding Current Maturities 2,487.4 2,413.3 2,444.8  
Accrued pension liability 0.0 0.0 0.0  
Deferred income taxes 237.9 223.6 294.7  
Long-term payables—affiliates 0.0 0.0 0.0  
Other Liabilities, Noncurrent 8.1 6.6 0.0  
Total liabilities 2,802.2 2,740.5 2,807.0  
Common Stock, Value, Issued 0.0 0.0 0.0  
Additional Paid in Capital, Common Stock 4,125.7 4,125.7 4,125.7  
Accumulated other comprehensive loss 0.0 0.0 0.0  
Retained Earnings (Accumulated Deficit) 25.3 38.1 6.9  
Total shareholders' equity 4,151.0 4,163.8 4,132.6  
Total liabilities and shareholders' equity 6,953.2 6,904.3 6,939.6  
Subsidiary Non-Guarantor        
Supplemental Guarantor Financial Information Balance Sheets [Line Items]        
Cash and cash equivalents 155.6 159.3 43.4 272.6
Receivables, net 680.5 586.7 692.3  
Intercompany receivables 2,052.9 1,912.3 1,712.1  
Income taxes receivable 7.2 7.3 10.7  
Inventories 488.0 462.7 461.0  
Other Assets, Current 7.0 1.2 5.4  
Total current assets 3,391.2 3,129.5 2,924.9  
Property, Plant and Equipment, Net 3,118.3 3,194.8 3,298.6  
Investment in subsidiaries 0.0 0.0 0.0  
Deferred income taxes 97.8 103.5 88.5  
Other Assets, Noncurrent 578.7 596.3 548.2  
Long-term receivables—affiliates 0.0 0.0 0.0  
Intangible Assets, Net 599.5 623.5 665.0  
Goodwill 1,153.2 1,151.7 1,192.1  
Total assets 8,938.7 8,799.3 8,717.3  
Current installments of long-term debt 12.1 12.4 12.2  
Accounts payable 603.7 527.4 476.6  
Intercompany payables 0.0 0.0 0.0  
Income taxes payable 12.2 8.3 7.6  
Accrued Liabilities, Current 296.6 277.5 287.9  
Total current liabilities 924.6 825.6 784.3  
Long-term Debt, Excluding Current Maturities 209.2 209.9 12.4  
Accrued pension liability 203.9 184.4 452.6  
Deferred income taxes 924.1 926.4 932.3  
Long-term payables—affiliates 919.9 985.1 985.1  
Other Liabilities, Noncurrent 55.2 63.8 70.9  
Total liabilities 3,236.9 3,195.2 3,237.6  
Common Stock, Value, Issued 14.6 14.6 15.1  
Additional Paid in Capital, Common Stock 4,808.2 4,808.2 4,756.4  
Accumulated other comprehensive loss (8.6) (7.0) (21.1)  
Retained Earnings (Accumulated Deficit) 887.6 788.3 729.3  
Total shareholders' equity 5,701.8 5,604.1 5,479.7  
Total liabilities and shareholders' equity 8,938.7 8,799.3 8,717.3  
Eliminations        
Supplemental Guarantor Financial Information Balance Sheets [Line Items]        
Cash and cash equivalents 0.0 0.0 0.0 $ 0.0
Receivables, net 0.0 0.0 0.0  
Intercompany receivables (2,055.8) (1,912.3) (1,734.4)  
Income taxes receivable (5.1) (0.8) 0.0  
Inventories 0.0 0.0 0.0  
Other Assets, Current (152.9) (138.5) (127.7)  
Total current assets (2,213.8) (2,051.6) (1,862.1)  
Property, Plant and Equipment, Net 0.0 0.0 0.0  
Investment in subsidiaries (9,856.7) (9,769.9) (9,612.3)  
Deferred income taxes (124.4) (117.5) (147.7)  
Other Assets, Noncurrent 0.0 0.0 0.0  
Long-term receivables—affiliates (2,204.3) (2,194.2) (2,262.4)  
Intangible Assets, Net 0.0 0.0 0.0  
Goodwill 0.0 0.0 0.0  
Total assets (14,399.2) (14,133.2) (13,884.5)  
Current installments of long-term debt 0.0 0.0 0.0  
Accounts payable (5.6) (1.9) 0.0  
Intercompany payables (2,055.8) (1,912.3) (1,734.4)  
Income taxes payable (5.1) (0.8) 0.0  
Accrued Liabilities, Current (151.2) (138.6) (127.7)  
Total current liabilities (2,217.7) (2,053.6) (1,862.1)  
Long-term Debt, Excluding Current Maturities 0.0 0.0 0.0  
Accrued pension liability 0.0 0.0 0.0  
Deferred income taxes (124.4) (117.5) (147.7)  
Long-term payables—affiliates (2,204.3) (2,194.2) (2,262.4)  
Other Liabilities, Noncurrent 0.0 0.0 0.0  
Total liabilities (4,546.4) (4,365.3) (4,272.2)  
Common Stock, Value, Issued (14.6) (14.6) (15.1)  
Additional Paid in Capital, Common Stock (8,933.9) (8,933.9) (8,882.1)  
Accumulated other comprehensive loss 8.6 7.0 21.1  
Retained Earnings (Accumulated Deficit) (912.9) (826.4) (736.2)  
Total shareholders' equity (9,852.8) (9,767.9) (9,612.3)  
Total liabilities and shareholders' equity $ (14,399.2) $ (14,133.2) $ (13,884.5)