Available-for-Sale Debt and Equity Investments - Maturities of Available-for-Sale Debt Investments (Details) - USD ($) $ in Millions	Jan. 28, 2023	Jul. 30, 2022
Amortized Cost
Within 1 year	$ 4,806
After 1 year through 5 years	6,491
After 5 years through 10 years	46
Mortgage-backed securities with no single maturity	2,013
Amortized Cost	13,356	$ 12,467
Fair Value
Within 1 year	4,734
After 1 year through 5 years	6,170
After 5 years through 10 years	41
Mortgage-backed securities with no single maturity	1,827
Fair Value	$ 12,772	$ 11,947

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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