Available-for-Sale Debt and Equity Investments - Maturities of Available-for-Sale Debt Investments (Details) - USD ($) $ in Millions	Apr. 30, 2022	Jul. 31, 2021
Amortized Cost
Within 1 year	$ 3,431
After 1 year through 5 years	7,619
After 5 years through 10 years	146
After 10 years	1
Mortgage-backed securities with no single maturity	2,234
Amortized Cost	13,431	$ 14,978
Fair Value
Within 1 year	3,397
After 1 year through 5 years	7,319
After 5 years through 10 years	139
After 10 years	1
Mortgage-backed securities with no single maturity	2,058
Fair Value	$ 12,914	$ 15,206

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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