Marketable Securities - Current and Non-current (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Marketable Securities
Current marketable securities	$ 805	$ 404
Non-current marketable securities	31	30
Total marketable securities	836	434
Corporate debt securities
Marketable Securities
Current marketable securities	7	7
Commercial paper
Marketable Securities
Current marketable securities	502	237
Certificates of deposit/time deposits
Marketable Securities
Current marketable securities	13	31
U.S. treasury securities
Marketable Securities
Current marketable securities	280	125
U.S. municipal securities
Marketable Securities
Current marketable securities	3	4
Non-current marketable securities	$ 31	$ 30

Amount of investment in marketable security.

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