Marketable Securities (current and non-current) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Marketable Securities
Current marketable securities	$ 385	$ 1,076
Non-current marketable securities	26	27
Total marketable securities	411	1,103
Corporate debt securities
Marketable Securities
Current marketable securities		14
Commercial paper
Marketable Securities
Current marketable securities	347	899
Certificates of deposit/time deposits
Marketable Securities
Current marketable securities	31	76
U.S. municipal securities
Marketable Securities
Current marketable securities	4	3
Non-current marketable securities	26	27
Asset-backed securities total
Marketable Securities
Current marketable securities	3	84
Asset-backed securities Automobile loan related
Marketable Securities
Current marketable securities	$ 3	16
Asset-backed securities Credit card related
Marketable Securities
Current marketable securities		$ 68

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

+ References

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Total debt and equity financial instruments including: (1) securities held-to-maturity and (2) securities available-for-sale that will be held for the long-term.

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