Available-for-Sale Debt and Equity Investments - Maturities of Fixed Income Securities (Details) - USD ($) $ in Millions	Jul. 25, 2020	Jul. 27, 2019
Amortized Cost
Within 1 year	$ 5,773
After 1 year through 5 years	7,360
After 5 years through 10 years	2,032
After 10 years	11
Mortgage-backed securities with no single maturity	1,987
Amortized Cost	17,163	$ 21,590
Fair Value
Within 1 year	5,812
After 1 year through 5 years	7,532
After 5 years through 10 years	2,218
After 10 years	13
Mortgage-backed securities with no single maturity	2,035
Total	$ 17,610	$ 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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