Taxes (Reconciliation of Unrecognized Tax Benefits from Continuing Operations) (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Reconciliation of Unrecognized Tax Benefits
Gross unrecognized tax benefits, beginning of year	$ 3,135	$ 1,817	$ 1,305
Increases related to prior year tax positions	170	92	516
Decreases related to prior year tax positions	(97)	(264)	(15)
Increases related to current year tax positions	75	1,582	66
Settlements during the period	(5)	(64)	(29)
Lapse in statutes of limitations	(33)	(28)	(26)
Gross unrecognized tax benefits, end of year	$ 3,245	$ 3,135	$ 1,817

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.

+ References

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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