Cash Equivalents and Marketable Securities - Amortized Cost and Estimated Fair Value of Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions |
Jan. 26, 2020 |
Jan. 27, 2019 |
|---|---|---|
| Amortized Cost | ||
| Less than one year | $ 10,781 | $ 5,042 |
| Due in 1 - 5 years | 0 | 2,271 |
| Mortgage-backed securities issued by United States government-sponsored enterprises not due at a single maturity date | 0 | 22 |
| Amortized Cost | 10,781 | 7,335 |
| Estimated Fair Value | ||
| Less than one year | 10,781 | 5,034 |
| Due in 1 - 5 years | 0 | 2,268 |
| Mortgage-backed securities issued by United States government-sponsored enterprises not due at a single maturity date | 0 | 22 |
| Estimated Fair Value | $ 10,781 | $ 7,324 |
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition 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 second through fifth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value 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 second through fifth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amortized cost of investment in debt security measured at fair value with change recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), maturing in next fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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