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LONG-TERM DEBT (Break-Down of Long-Term Debt) (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Debt Instrument [Line Items] |  |
Net unamortized debt issuance costs | $ (19,772) | $ (23,751)
Less: current maturities of long term debt | (656) | (631)
Debt reflected as long term | 2,068,036 | 1,978,020
Construction Loan |  |
Debt Instrument [Line Items] |  |
Net unamortized debt issuance costs | (100) |
6.625% senior unsecured notes due 2023 | Senior Notes |  |
Debt Instrument [Line Items] |  |
Long-term debt | 324,583 | 329,467
Net unamortized debt issuance costs | $ (2,600) |
Stated interest rate, percent | 6.625% |
6.000% senior unsecured notes due 2024 | Senior Notes |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 579,568 | 603,428
Net unamortized debt issuance costs | $ (5,700) |
Stated interest rate, percent | 6.00% |
6.375% senior unsecured notes due 2025 | Senior Notes |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 507,870 | 529,525
Net unamortized debt issuance costs | $ (8,100) |
Stated interest rate, percent | 6.375% |
6.375% senior unsecured notes due 2026 | Senior Notes |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 374,617 | 397,529
Net unamortized debt issuance costs | $ (3,300) |
Stated interest rate, percent | 6.375% |
Nova Scotia, Amegy, KeyBank | Revolving Credit Agreement | Revolving Credit Agreement |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 279,857 | 120,000
InterBank | Letter of Credit | Construction Loan |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 21,969 | $ 22,453

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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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