Marketable Securities and Held-to-Maturity Debt Securities - Current and non-current (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Marketable Securities
Current marketable securities	$ 440	$ 98
Non-current marketable securities	34	43
Total marketable securities	474	141
Corporate debt securities
Marketable Securities
Current marketable securities	7
Commercial paper
Marketable Securities
Current marketable securities	233	85
Certificates of deposit/time deposits
Marketable Securities
Current marketable securities	47	10
U.S. treasury securities
Marketable Securities
Current marketable securities	150
U.S. municipal securities
Marketable Securities
Current marketable securities	3	3
Non-current marketable securities	$ 34	$ 43

Amount of investment in marketable security.

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