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FAIR VALUE MEASUREMENTS - Carrying Amounts of Long-term Debt (Details) - USD ($) $ in Millions	12 Months Ended
	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.

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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
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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

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-Publisher FASB
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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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