LONG-TERM DEBT (4.875% Senior Notes) (Details) - 4.875% Senior Notes Due 2024 [Member] - USD ($)  | 
12 Months Ended | |
|---|---|---|
Dec. 31, 2017  | 
Oct. 31, 2016  | 
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| Debt Instrument [Line Items] | ||
| Face amount | $ 575,000,000 | $ 575,000,000 | 
| Interest rate, stated percentage | 4.875% | 4.875% | 
| Prior to November 1, 2019 [Member] | ||
| Debt Instrument [Line Items] | ||
| Redemption price, percentage | 100.00% | |
| Redemption, Equity Offering [Member] | ||
| Debt Instrument [Line Items] | ||
| Redemption price, percentage | 104.875% | |
| Percentage of notes which may be redeemed | 35.00% | |
| After November 1, 2019 [Member] | ||
| Debt Instrument [Line Items] | ||
| Redemption price, percentage | 103.656% | |
| Redemption, Defined Changes of Control [Member] | ||
| Debt Instrument [Line Items] | ||
| Redemption price, percentage | 101.00% | 
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- Definition Represents the percentage of the notes which may be redeemed from the proceeds of certain equity offerings prior to maturity as defined in the loan agreement. No definition available. 
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Definition Percentage price of original principal amount of debt at which debt can be redeemed by the issuer. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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