Available-for-Sale Debt and Equity Investments - Maturities of Available-for-Sale Debt Investments (Details) - USD ($) $ in Millions	May 01, 2021	Jul. 25, 2020
Amortized Cost
Within 1 year	$ 5,608
After 1 year through 5 years	6,296
After 5 years through 10 years	1,244
After 10 years	5
Mortgage-backed securities with no single maturity	2,788
Amortized Cost	15,941	$ 17,163
Fair Value
Within 1 year	5,605
After 1 year through 5 years	6,428
After 5 years through 10 years	1,318
After 10 years	7
Mortgage-backed securities with no single maturity	2,810
Fair Value	$ 16,168	$ 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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