Marketable Securities and Held-to-Maturity Debt Securities - Current and non-current (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Held-to-Maturity Debt Securities
Current marketable securities	$ 98	$ 380
Non-current marketable securities	43	37
Total marketable securities	141	417
Commercial paper
Held-to-Maturity Debt Securities
Current marketable securities	85	366
Certificates of deposit/time deposits
Held-to-Maturity Debt Securities
Current marketable securities	10	10
U.S. municipal securities
Held-to-Maturity Debt Securities
Current marketable securities	3	3
Non-current marketable securities	$ 43	37
Asset-backed securities
Held-to-Maturity Debt Securities
Current marketable securities		$ 1

Amount of investment in marketable security.

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-SubTopic 210
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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