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DEBT DEBT (Details) $ in Thousands |  | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Nov. 01, 2021 USD ($) Rate | Jun. 30, 2021 USD ($) | Mar. 31, 2021 USD ($) | Sep. 30, 2021 USD ($) Rate | Oct. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) Rate
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 14,292,816 |  | $ 14,361,644
Unamortized portion of terminated swaps |  |  |  | 12,025 |  | 13,314
Unamortized debt issuance costs and discounts |  |  |  | (128,267) |  | (138,887)
Current maturities of long-term debt |  |  |  | (536,107) |  | (7,650)
Long-term debt |  |  |  | 13,640,467 |  | 14,228,421
Long-term Debt, Repurchased Face Amount |  |  | $ 55,200 |  |  |
Repayments of Debt |  |  | $ 54,600 |  |  |
$2.5 Billion Credit Agreement [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  |  |  | 2,500,000 |  |
Line of Credit Facility, Amount Outstanding |  |  |  | $ 0 |  |
Debt Instrument, Covenant Description |  |  |  | Among other things, these covenants include maintaining a ratio of indebtedness to adjusted EBITDA (EBITDA, as defined in our $2.5 Billion Credit Agreement, adjusted for all noncash charges and increased for projected EBITDA from certain lender-approved capital expansion projects) of no more than 5.0 to 1 at September 30, 2021. |  |
Indebtedness To Adjusted EBITDA Maximum |  |  |  | 5.0 |  |
Indebtedness To Adjusted EBITDA Current |  |  |  | 4.3 |  |
Guardian Pipeline [Member] | Notes Payables due 2022 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 0 |  | $ 13,657
Average interest rate (in hundredths) | Rate |  |  |  |  |  | 7.85%
Repayments of Debt |  | $ 11,700 |  |  |  |
Subsidiary Issuer [Member] | 3.375% Notes Payable due 2022 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | 895,814 |  | $ 895,814
Debt Instrument, Face Amount |  |  |  | $ 900,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 3.375% |  |
Subsidiary Issuer [Member] | 5.0% Notes Payable due 2023 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 425,000 |  | 425,000
Debt Instrument, Face Amount |  |  |  | $ 425,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 5.00% |  |
Subsidiary Issuer [Member] | 4.9% Notes Payable due 2025 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 500,000 |  | 500,000
Debt Instrument, Face Amount |  |  |  | $ 500,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 4.90% |  |
Subsidiary Issuer [Member] | 6.65% Notes Payable due 2036 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 600,000 |  | 600,000
Debt Instrument, Face Amount |  |  |  | $ 600,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 6.65% |  |
Subsidiary Issuer [Member] | 6.85% Notes Payable due 2037 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 600,000 |  | 600,000
Debt Instrument, Face Amount |  |  |  | $ 600,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 6.85% |  |
Subsidiary Issuer [Member] | 6.125% Notes Payable due 2041 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 650,000 |  | 650,000
Debt Instrument, Face Amount |  |  |  | $ 650,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 6.125% |  |
Subsidiary Issuer [Member] | 6.2% Notes Payable due 2043 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 400,000 |  | 400,000
Debt Instrument, Face Amount |  |  |  | $ 400,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 6.20% |  |
Parent Company |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Commercial paper |  |  |  | $ 0 |  | 0
Parent Company | Subsequent Event [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Commercial paper |  |  |  |  | $ 150,000 |
Parent Company | 4.25% Notes Payable due 2022 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | 536,107 |  | 541,877
Debt Instrument, Face Amount |  |  |  | $ 700,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 4.25% |  |
Parent Company | 4.25% Notes Payable due 2022 [Member] | Subsequent Event [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt Instrument, Face Amount | $ 700,000 |  |  |  |  |
Interest Rate (in hundredths) | Rate | 4.25% |  |  |  |  |
Repayments of Debt | $ 536,100 |  |  |  |  |
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed | 100.00% |  |  |  |  |
Parent Company | 7.5% Notes Payable due 2023 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 500,000 |  | 500,000
Debt Instrument, Face Amount |  |  |  | $ 500,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 7.50% |  |
Parent Company | 2.75% Notes Payable due 2024 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 500,000 |  | 500,000
Debt Instrument, Face Amount |  |  |  | $ 500,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 2.75% |  |
Parent Company | 2.2% Notes Payable due 2025 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 387,000 |  | 387,000
Debt Instrument, Face Amount |  |  |  | $ 400,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 2.20% |  |
Parent Company | 5.85% Notes Payable due 2026 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 600,000 |  | 600,000
Debt Instrument, Face Amount |  |  |  | $ 600,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 5.85% |  |
Parent Company | 4.0% Notes Payable due 2027 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 500,000 |  | 500,000
Debt Instrument, Face Amount |  |  |  | $ 500,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 4.00% |  |
Parent Company | 4.55% Notes Payable due 2028 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 800,000 |  | 800,000
Debt Instrument, Face Amount |  |  |  | $ 800,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 4.55% |  |
Parent Company | 6.875% Notes Payable due 2028 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 100,000 |  | 100,000
Debt Instrument, Face Amount |  |  |  | $ 100,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 6.875% |  |
Parent Company | 4.35% Notes Payable due 2029 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 700,000 |  | 700,000
Debt Instrument, Face Amount |  |  |  | $ 700,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 4.35% |  |
Parent Company | 3.4% Notes Payable due 2029 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 714,251 |  | 714,251
Debt Instrument, Face Amount |  |  |  | $ 750,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 3.40% |  |
Parent Company | 3.1% Notes Payable due 2030 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 780,093 |  | 780,093
Debt Instrument, Face Amount |  |  |  | $ 850,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 3.10% |  |
Parent Company | 6.35% Notes Payable due 2031 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 600,000 |  | 600,000
Debt Instrument, Face Amount |  |  |  | $ 600,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 6.35% |  |
Parent Company | 6.0% Notes Payable due 2035 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 400,000 |  | 400,000
Debt Instrument, Face Amount |  |  |  | $ 400,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 6.00% |  |
Parent Company | 4.95% Notes Payable due 2047 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 689,006 |  | 689,006
Debt Instrument, Face Amount |  |  |  | $ 700,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 4.95% |  |
Parent Company | 5.2% Notes Payable due 2048 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 1,000,000 |  | 1,000,000
Debt Instrument, Face Amount |  |  |  | $ 1,000,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 5.20% |  |
Parent Company | 4.45% Notes Payable due 2049 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 672,530 |  | 713,676
Debt Instrument, Face Amount |  |  |  | $ 750,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 4.45% |  |
Parent Company | 4.5% Notes Payable due 2050 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 443,015 |  | 451,270
Debt Instrument, Face Amount |  |  |  | $ 500,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 4.50% |  |
Parent Company | 7.15% Notes Payable due 2051 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Total debt |  |  |  | $ 300,000 |  | $ 300,000
Debt Instrument, Face Amount |  |  |  | $ 300,000 |  |
Interest Rate (in hundredths) | Rate |  |  |  | 7.15% |  |

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