Available-for-Sale Debt Securities - Summary of Available-for-Sale Debt Securities by Contractual Maturity (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Amortized Cost
Within one year	$ 12,623
After one year through five years	2,197
After five years	64
Total	14,884	$ 16,499
Fair Value
Within one year	12,659
After one year through five years	2,212
After five years	64
Total	$ 14,935	$ 16,500

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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