| LONG-TERM DEBT (5.625% Senior Notes) (Details) - 5.625% Senior Notes Due 2026 [Member] - USD ($) | 12 Months Ended | |
|---|---|---|
| Dec. 31, 2020 | Mar. 31, 2019 | |
| Debt Instrument [Line Items] | ||
| Face amount | $ 300,000,000 | $ 300,000,000 | 
| Interest rate, stated percentage | 5.625% | 5.625% | 
| Redemption Period Prior Stated Date [Member] | ||
| Debt Instrument [Line Items] | ||
| Redemption price, percentage | 100.00% | |
| Redemption, Equity Offerings [Member] | ||
| Debt Instrument [Line Items] | ||
| Redemption price, percentage | 105.625% | |
| Percentage of notes which may be redeemed | 35.00% | |
| Redemption Period After Stated Date [Member] | ||
| Debt Instrument [Line Items] | ||
| Redemption price, percentage | 104.219% | |
| 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://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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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://fasb.org/us-gaap/role/ref/legacyRef 
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