Available-for-Sale Debt and Equity Investments - Maturities of Fixed Income Securities (Details) - USD ($) $ in Millions	Oct. 24, 2020	Jul. 25, 2020
Amortized Cost
Within 1 year	$ 7,480
After 1 year through 5 years	6,897
After 5 years through 10 years	1,943
After 10 years	9
Mortgage-backed securities with no single maturity	2,494
Amortized Cost	18,823	$ 17,163
Fair Value
Within 1 year	7,490
After 1 year through 5 years	7,052
After 5 years through 10 years	2,109
After 10 years	10
Mortgage-backed securities with no single maturity	2,529
Total	$ 19,190	$ 17,610

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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