Financial Instruments and Fair Value Measurement - Schedule of Contractual Maturities of Marketable Securities (Details) - Recurring - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Amortized Cost
Due within one year	$ 164	$ 300
Due after one year through five years	4	34
Total marketable securities	168	334
Estimated Fair Value
Due within one year	164	300
Due after one year through five years	4	34
Total marketable securities	$ 168	$ 334

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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