Available-for-Sale Debt Investments and Equity Investments - Maturities of Fixed Income Securities (Details) - USD ($) $ in Millions	Jan. 25, 2020	Jul. 27, 2019
Amortized Cost
Within 1 year	$ 5,704
After 1 year through 5 years	8,898
After 5 years through 10 years	2,150
After 10 years	7
Mortgage-backed securities with no single maturity	1,612
Amortized Cost	18,371	$ 21,590
Fair Value
Within 1 year	5,717
After 1 year through 5 years	8,995
After 5 years through 10 years	2,245
After 10 years	7
Mortgage-backed securities with no single maturity	1,623
Total	$ 18,587	$ 21,660

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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