Debt (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total debt principal	$ 14,026	$ 12,518
Less unamortized debt issuance costs and discounts	91	101
Total debt	13,935	12,417
Less current portion	4,960	973
Long-term debt	8,975	11,444
Commercial Paper
Debt Instrument [Line Items]
Short term debt	$ 2,250	850
Weighted average interest rate	2.482%
Fixed Rate Notes Due May 2020
Debt Instrument [Line Items]
Long term debt	$ 2,000	2,000
Interest rate	2.875%
Fixed Rate Notes Due May 2021
Debt Instrument [Line Items]
Long term debt	$ 2,000	2,000
Interest rate	3.00%
Fixed-Rate Notes Due July 2021
Debt Instrument [Line Items]
Long term debt	$ 500	500
Interest rate	3.875%
Fixed Rate Notes Due November 2022
Debt Instrument [Line Items]
Long term debt	$ 1,000	1,000
Interest rate	2.25%
Fixed Rate Notes Due May 2023
Debt Instrument [Line Items]
Long term debt	$ 750	750
Interest rate	3.375%
Fixed Rate Notes Due August 2023
Debt Instrument [Line Items]
Long term debt	$ 500	500
Interest rate	1.875%
Fixed Rate Notes Due November 2024
Debt Instrument [Line Items]
Long term debt	$ 500	500
Interest rate	2.375%
Fixed Rate Notes Due May 2025
Debt Instrument [Line Items]
Long term debt	$ 750	750
Interest rate	3.50%
Fixed Rate Notes Due August 2026
Debt Instrument [Line Items]
Long term debt	$ 500	500
Interest rate	2.125%
Fixed Rate Notes Due November 2027
Debt Instrument [Line Items]
Long term debt	$ 500	500
Interest rate	2.625%
Fixed Rate Notes Due May 2028
Debt Instrument [Line Items]
Long term debt	$ 1,000	1,000
Interest rate	3.75%
Fixed Rate Notes Due November 2042
Debt Instrument [Line Items]
Long term debt	$ 500	500
Interest rate	3.60%
Floating Rate Notes Due May 2020 \| LIBOR
Debt Instrument [Line Items]
Long term debt	$ 500	500
Basis spread on variable rate	0.29%
Floating Rate Notes Due May 2021 \| LIBOR
Debt Instrument [Line Items]
Long term debt	$ 500	500
Basis spread on variable rate	0.38%
Other Debt Securities
Debt Instrument [Line Items]
Long term debt	$ 276	$ 168
Other Interest rate	Various

Debt Instrument Interest Rate

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- Definition

Debt, Long-term and Short-term, Combined Amount, Excluding Current Maturities

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- Definition

Debt, Long-term and Short-term, Combined Amount, Net

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Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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- Definition

Weighted average interest rate of short-term debt outstanding calculated at point in time.

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