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FAIR VALUE MEASUREMENTS - Carrying Amounts of Long-term Debt (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Fair value and related carrying amounts of long-term debt and other long-term obligations |  |  |
Debt issuances | $ 3,425 | $ 2,300 | $ 1,474
Debt redemptions | 1,114 | 789 | $ 2,608
Carrying Value |  |  |
Fair value and related carrying amounts of long-term debt and other long-term obligations |  |  |
Long-term debt and other long-term obligations | 22,377 | 20,066 |
Debt issuances | 3,425 |  |
Debt redemptions | 1,114 |  |
Fair Value |  |  |
Fair value and related carrying amounts of long-term debt and other long-term obligations |  |  |
Long-term debt and other long-term obligations | $ 25,465 | $ 22,928 |

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- Definition Fair value and related carrying amounts of long-term debt and other long-term obligations. + References No definition available. + Details
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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + 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)(3) -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(a)(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 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 4: 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 + Details
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