Debt Outstanding Debt (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Total Borrowings at Par Value	$ 21,175	$ 16,701
Fair Value Hedge Accounting Adjustments	(70)	(50)
Unamortized (Discount) Premium, Net	(2)	52
Unamortized Debt Issuance Costs	(95)	(76)
Total Borrowings at Carrying Value	21,008	16,627
Less: Short-term Obligations and Current Maturities	2,135	1,255
Long-term Obligations	$ 18,873	15,372
Commercial Paper Programs [Member]
Debt Instrument [Line Items]
Effective Interest Rate	(0.26%)
Total Borrowings at Par Value	$ 960	953
Total Borrowings at Carrying Value	960	953
Term Loan [Member]
Debt Instrument [Line Items]
Total Borrowings at Par Value		825
Total Borrowings at Carrying Value		823
Senior Notes [Member]
Debt Instrument [Line Items]
Total Borrowings at Carrying Value	$ 20,024	14,838
Debt Instrument, Call Feature	Each of the notes may be redeemed at a redemption price of 100% of the principal amount plus a specified make-whole premium plus accrued interest.
Senior Notes [Member] \| 1.85% 5-Year Senior Notes, Due 1/15/2018 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	1.85%
Debt Instrument, Term	5 years
Debt Instrument, Maturity Date	Jan. 15, 2018
Total Borrowings at Par Value		500
Senior Notes [Member] \| Floating Rate 2-Year Senior Notes, Due 8/9/2018 (euro-denominated) [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	2 years
Debt Instrument, Maturity Date	Aug. 09, 2018
Effective Interest Rate	0.37%
Total Borrowings at Par Value	$ 721	631
Senior Notes [Member] \| 2.15% 3-Year Senior Notes, Due 12/14/2018 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	2.15%
Debt Instrument, Term	3 years
Debt Instrument, Maturity Date	Dec. 14, 2018
Effective Interest Rate	2.35%
Total Borrowings at Par Value	$ 450	450
Senior Notes [Member] \| 2.40% 5-Year Senior Notes, Due 2/1/2019 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	2.40%
Debt Instrument, Term	5 years
Debt Instrument, Maturity Date	Feb. 01, 2019
Effective Interest Rate	2.59%
Total Borrowings at Par Value	$ 900	900
Senior Notes [Member] \| Floating Rate 2-Year Senior Notes, Due 7/24/2019 (euro-denominated) [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	2 years
Debt Instrument, Maturity Date	Jul. 24, 2019
Effective Interest Rate	0.10%
Total Borrowings at Par Value	$ 600
Senior Notes [Member] \| 6.00% 10-Year Senior Notes, Due 3/1/2020 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	6.00%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	Mar. 01, 2020
Effective Interest Rate	2.97%
Total Borrowings at Par Value	$ 750	750
Senior Notes [Member] \| 4.70% 10-Year Senior Notes, Due 5/1/2020 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	4.70%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	May 01, 2020
Effective Interest Rate	4.23%
Total Borrowings at Par Value	$ 300	300
Senior Notes [Member] \| 1.50% 5-Year Senior Notes, Due 12/1/2020 (euro-denominated) [Member]
Debt Instrument [Line Items]
Stated Interest Rate	1.50%
Debt Instrument, Term	5 years
Debt Instrument, Maturity Date	Dec. 01, 2020
Effective Interest Rate	1.62%
Total Borrowings at Par Value	$ 510	447
Senior Notes [Member] \| 5.00% 10-Year Senior Notes, Due 1/15/2021 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	5.00%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	Jan. 15, 2021
Effective Interest Rate	3.24%
Total Borrowings at Par Value	$ 400	400
Senior Notes [Member] \| 4.50% 10-Year Senior Notes, Due 3/1/2021 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	4.50%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	Mar. 01, 2021
Effective Interest Rate	5.37%
Total Borrowings at Par Value	$ 1,000	1,000
Senior Notes [Member] \| 3.60% 10-Year Senior Notes, Due 8/15/2021 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	3.60%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	Aug. 15, 2021
Effective Interest Rate	5.19%
Total Borrowings at Par Value	$ 1,100	1,100
Senior Notes [Member] \| 3.30% 7-Year Senior Notes, Due 2/15/2022 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	3.30%
Debt Instrument, Term	7 years
Debt Instrument, Maturity Date	Feb. 15, 2022
Effective Interest Rate	3.43%
Total Borrowings at Par Value	$ 800	800
Senior Notes [Member] \| 2.15% 7-Year Senior Notes, Due 7/21/2022 (euro-denominated) [Member]
Debt Instrument [Line Items]
Stated Interest Rate	2.15%
Debt Instrument, Term	7 years
Debt Instrument, Maturity Date	Jul. 21, 2022
Effective Interest Rate	2.28%
Total Borrowings at Par Value	$ 600	526
Senior Notes [Member] \| 3.15% 10-Year Senior Notes, Due 1/15/2023 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	3.15%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	Jan. 15, 2023
Effective Interest Rate	3.31%
Total Borrowings at Par Value	$ 800	800
Senior Notes [Member] \| 3.00% 7-Year Senior Notes, Due 4/15/2023 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	3.00%
Debt Instrument, Term	7 years
Debt Instrument, Maturity Date	Apr. 15, 2023
Effective Interest Rate	5.42%
Total Borrowings at Par Value	$ 1,000	1,000
Senior Notes [Member] \| 4.15% 10-Year Senior Notes, Due 2/1/2024 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	4.15%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	Feb. 01, 2024
Effective Interest Rate	4.16%
Total Borrowings at Par Value	$ 1,000	1,000
Senior Notes [Member] \| 0.75% 8-Year Senior Notes, Due 9/12/2024 (euro-denominated) [Member]
Debt Instrument [Line Items]
Stated Interest Rate	0.75%
Debt Instrument, Term	8 years
Debt Instrument, Maturity Date	Sep. 12, 2024
Effective Interest Rate	0.95%
Total Borrowings at Par Value	$ 1,201	1,052
Senior Notes [Member] \| 2.00% 10-Year Senior Notes, Due 4/15/2025 (euro-denominated) [Member]
Debt Instrument [Line Items]
Stated Interest Rate	2.00%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	Apr. 15, 2025
Effective Interest Rate	2.10%
Total Borrowings at Par Value	$ 768	673
Senior Notes [Member] \| 3.65% 10-Year Senior Notes, Due 12/15/2025 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	3.65%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	Dec. 15, 2025
Effective Interest Rate	3.77%
Total Borrowings at Par Value	$ 350	350
Senior Notes [Member] \| 1.40% 8.5-Year Senior Notes, Due 1/23/2026 (euro-denominated) [Member]
Debt Instrument [Line Items]
Stated Interest Rate	1.40%
Debt Instrument, Term	8 years 6 months
Debt Instrument, Maturity Date	Jan. 23, 2026
Effective Interest Rate	1.53%
Total Borrowings at Par Value	$ 840
Senior Notes [Member] \| 2.95% 10-Year Senior Notes, Due 9/19/2026 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	2.95%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	Sep. 19, 2026
Effective Interest Rate	3.19%
Total Borrowings at Par Value	$ 1,200	1,200
Senior Notes [Member] \| 1.45% 10-Year Senior Notes, Due 3/16/2027 (euro-denominated) [Member]
Debt Instrument [Line Items]
Stated Interest Rate	1.45%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	Mar. 16, 2027
Effective Interest Rate	1.66%
Total Borrowings at Par Value	$ 600
Senior Notes [Member] \| 3.20% 10-Year Senior Notes, Due 8/15/2027 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	3.20%
Debt Instrument, Term	10 years
Debt Instrument, Maturity Date	Aug. 15, 2027
Effective Interest Rate	3.39%
Total Borrowings at Par Value	$ 750
Senior Notes [Member] \| 1.375% 12-Year Senior Notes, Due 9/12/2028 (euro-denominated) [Member]
Debt Instrument [Line Items]
Stated Interest Rate	1.375%
Debt Instrument, Term	12 years
Debt Instrument, Maturity Date	Sep. 12, 2028
Effective Interest Rate	1.46%
Total Borrowings at Par Value	$ 721	631
Senior Notes [Member] \| 1.95% 12-Year Senior Notes, Due 7/24/2029 (euro-denominated) [Member]
Debt Instrument [Line Items]
Stated Interest Rate	1.95%
Debt Instrument, Term	12 years
Debt Instrument, Maturity Date	Jul. 24, 2029
Effective Interest Rate	2.08%
Total Borrowings at Par Value	$ 840
Senior Notes [Member] \| 2.875% 20-Year Senior Notes, Due 7/24/2037 (euro-denominated) [Member]
Debt Instrument [Line Items]
Stated Interest Rate	2.875%
Debt Instrument, Term	20 years
Debt Instrument, Maturity Date	Jul. 24, 2037
Effective Interest Rate	2.94%
Total Borrowings at Par Value	$ 840
Senior Notes [Member] \| 5.30% 30-Year Senior Notes, Due 2/1/2044 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	5.30%
Debt Instrument, Term	30 years
Debt Instrument, Maturity Date	Feb. 01, 2044
Effective Interest Rate	5.37%
Total Borrowings at Par Value	$ 400	400
Senior Notes [Member] \| 4.10% 30-Year Senior Notes, Due 8/15/2047 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	4.10%
Debt Instrument, Term	30 years
Debt Instrument, Maturity Date	Aug. 15, 2047
Effective Interest Rate	4.23%
Total Borrowings at Par Value	$ 750
Other Debt [Member]
Debt Instrument [Line Items]
Total Borrowings at Par Value	24	13
Total Borrowings at Carrying Value	$ 24	$ 13

Adjustment to the carrying value of an interest-bearing hedged item resulting from an interest rate fair value hedge.

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- Definition

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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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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- Definition

Description of a feature that permits the issuer of the debt to repay or convert it before the stated maturity date (early retirement date). The description may include such items as the call price, the period that the issuer can call the debt, including the earliest call date, and other significant terms of the call feature, which may include the debt holders' ability to convert the debt to equity if the call option is exercised and contingent events that trigger the issuer's ability to call the debt.

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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.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

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

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- Definition

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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No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Amount, after accumulated amortization, of debt discount (premium).

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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