Available-for-Sale Debt and Equity Investments - Maturities of Available-for-Sale Debt Investments (Details) - USD ($) $ in Millions	Jan. 23, 2021	Jul. 25, 2020
Amortized Cost
Within 1 year	$ 6,674
After 1 year through 5 years	7,035
After 5 years through 10 years	1,913
After 10 years	8
Mortgage-backed securities with no single maturity	2,796
Amortized Cost	18,426	$ 17,163
Fair Value
Within 1 year	6,679
After 1 year through 5 years	7,201
After 5 years through 10 years	2,060
After 10 years	10
Mortgage-backed securities with no single maturity	2,840
Total	$ 18,790	$ 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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