Supplemental Financial Information (Supplemental Cash Flow Information) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Additional Financial Information Disclosure [Abstract]
Cash paid for interest	$ 322	$ 340
Cash paid for income taxes	55	197
Noncash additions to operating lease assets	$ 55	$ 179

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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- Definition

Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

+ References

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-Publisher FASB
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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Additional Financial Information Disclosure [Abstract]

+ References

No definition available.

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