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DEBT AND CREDIT FACILITIES (Narrative) (Details) $ / shares in Units, shares in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 USD ($) $ / shares | Dec. 31, 2018 USD ($) $ / shares | Dec. 31, 2017 USD ($) $ / shares shares
Debt Instrument [Line Items] |  |  |
Debt Instrument, Par Value | $ 2,238,000,000.0 |  |
Common shares, par value | $ / shares | $ 0.125 | $ 0.125 |
Debt Extinguished | $ 724,000,000.0 | $ 227,400,000 | $ 1,610,700,000
Net proceeds from issuance of common shares | $ 0 | 0 | $ 661,300,000
$400 Million 4.875% 2024 Senior Notes [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.875% |  |
Repurchase price if triggering event occurs | 101.00% |  |
Debt Instrument, Par Value | $ 400,000,000.0 | 400,000,000.0 |
$316.25 Million 1.50% 2025 Senior Notes [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 1.50% |  |
Debt Instrument, Par Value | $ 316,300,000 | $ 316,300,000 |
Common shares, par value | $ / shares | $ 0.125 |  |
Debt Instrument, Convertible, Threshold Trading Days | 20 |  |
Debt Instrument, Convertible, Threshold Consecutive Trading Days | 30 |  |
Convertible debt, principal increment | $ 1,000 |  |
Convertible debt, initial conversion price | $ / shares | $ 8.17 |  |
Debt Instrument, Convertible, Conversion Ratio | 126.3479 | 122.4365 |
Debt Instrument, Redemption Price, Percentage | 100.00% |  |
$316.25 Million 1.50% 2025 Senior Notes [Member] | Minimum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger | 130.00% |  |
$316.25 Million 1.50% 2025 Senior Notes [Member] | Maximum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger | 98.00% |  |
$1.075 Billion 5.75% 2025 Senior Notes [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.75% |  |
Debt Instrument, Par Value | $ 473,300,000 | $ 1,073,300,000 |
Debt Instrument, Redemption Price, Percentage | 100.00% |  |
Amount in aggregate that can be redeemed on or prior to March 1, 2020 | 0.35 |  |
Redemption Price of 35 percent or less of Outstanding | 1.0575 |  |
Debt Extinguished | $ 600,000,000.0 | 1,700,000 |
$750 Million 5.875% 2027 Senior Notes [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.875% |  |
Repurchase price if triggering event occurs | 101.00% |  |
Debt Instrument, Par Value | $ 750,000,000.0 |  |
Debt issuance, discount rate | 96.125% |  |
Debt Issuance Costs, Gross | $ 6,800,000 |  |
$800 Million 6.25% 2040 Senior Notes [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 6.25% |  |
Debt Instrument, Par Value | $ 298,400,000 | 298,400,000 |
Debt Instrument, Redemption Price, Percentage | 100.00% |  |
Basis points | 40 |  |
$800 Million 6.25% 2040 Senior Notes [Member] | Minimum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Time Period During Which Senior Notes May Be Redeemed at Company's Option, Number of Days From When Prior Notice Sent to Holders | 30 years |  |
$800 Million 6.25% 2040 Senior Notes [Member] | Maximum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Time Period During Which Senior Notes May Be Redeemed at Company's Option, Number of Days From When Prior Notice Sent to Holders | 60 years |  |
ABL Facility [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Par Value | $ 450,000,000.0 | $ 450,000,000.0 |
Sublimit for Issuers of Letters of Credit for U.S. Tranche | 248,800,000 |  |
Sublimit for U.S. Swingline Loans | $ 100,000,000.0 |  |
Fixed Charge Coverage Ratio | 1.0 |  |
Equity [Member] | $316.25 Million 1.50% 2025 Senior Notes [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Convertible debt, equity component | $ 85,900,000 |  |
Federal Funds Rate [Member] | ABL Facility [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Basis Spread on Variable Rate | 0.50% |  |
London Interbank Offered Rate (LIBOR) [Member] | ABL Facility [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Basis Spread on Variable Rate | 1.00% |  |
Prime Rate [Member] | ABL Facility [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Basis Spread on Variable Rate | 1.00% |  |
Common Stock [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Equity offering (in shares) | shares |  |  | 63.3
Common stock, shares issued, price per share | $ / shares |  |  | $ 10.75

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