Available-for-Sale Debt Investments and Equity Investments - Maturities of Fixed Income Securities (Details) - USD ($) $ in Millions	Oct. 26, 2019	Jul. 27, 2019
Amortized Cost
Within 1 year	$ 5,472
After 1 year through 5 years	10,604
After 5 years through 10 years	1,709
After 10 years	6
Mortgage-backed securities with no single maturity	1,509
Amortized Cost	19,300	$ 21,590
Fair Value
Within 1 year	5,481
After 1 year through 5 years	10,676
After 5 years through 10 years	1,773
After 10 years	5
Mortgage-backed securities with no single maturity	1,510
Total	$ 19,445	$ 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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