Fair Value Measurements (Details 5) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair value and related carrying amounts of long-term debt and other long-term obligations
Debt issuances	$ 2,300	$ 1,474	$ 4,675
Debt redemptions	789	2,608	$ 2,291
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	22,928	19,266
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	20,074	$ 18,315
Debt issuances	2,300
Debt redemptions	$ 789

Fair value and related carrying amounts of long-term debt and other long-term obligations.

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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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-Publisher FASB
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+ Details

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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