Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Jan. 26, 2020 |
Jan. 27, 2019 |
Jan. 28, 2018 |
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| Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] | |||
| Balance at beginning of period | $ 477 | $ 447 | $ 224 |
| Increases in tax positions for prior years | 7 | 52 | 7 |
| Decreases in tax positions for prior years | 0 | (141) | (1) |
| Increases in tax positions for current year | 104 | 129 | 222 |
| Lapse in statute of limitations | (5) | (10) | (5) |
| Balance at end of period | $ 583 | $ 477 | $ 447 |
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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