Investments - Maturities of Fixed Income Securities (Details) - USD ($) $ in Millions	Jul. 29, 2023	Jul. 30, 2022
Amortized Cost
Within 1 year	$ 5,510
After 1 year through 5 years	8,197
After 5 years through 10 years	69
After 10 years	2
Mortgage-backed securities with no single maturity	2,421
Amortized Cost	16,199	$ 12,467
Fair Value
Within 1 year	5,462
After 1 year through 5 years	7,856
After 5 years through 10 years	67
After 10 years	2
Mortgage-backed securities with no single maturity	2,205
Fair Value	$ 15,592	$ 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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