Shareholders' Equity (Rollforward of Activity by Award Type) (Details) shares in Thousands	12 Months Ended
Jan. 31, 2022 $ / shares shares
Restricted Stock [Member]
Shares
Beginning balance (in shares) \| shares	19,900
Granted (in shares) \| shares	8,219
Adjustment for performance achievement (in shares) \| shares	0
Vested/exercised (in shares) \| shares	(8,051)
Forfeited (in shares) \| shares	(2,785)
Ending balance (in shares) \| shares	17,283
Weighted-Average Grant-Date Fair Value Per Share
Beginning balance (in USD per share) \| $ / shares	$ 92.13
Granted (in USD per share) \| $ / shares	131.90
Adjustment for performance achievement (in USD per share) \| $ / shares	0
Vested/exercised (in USD per share) \| $ / shares	85.21
Forfeited (in USD per share) \| $ / shares	110.65
Ending balance (in USD per share) \| $ / shares	$ 111.42
Restricted Stock And Performance Share Awards [Member]
Shares
Beginning balance (in shares) \| shares	5,413
Granted (in shares) \| shares	3,057
Adjustment for performance achievement (in shares) \| shares	920
Vested/exercised (in shares) \| shares	(2,614)
Forfeited (in shares) \| shares	(636)
Ending balance (in shares) \| shares	6,140
Weighted-Average Grant-Date Fair Value Per Share
Beginning balance (in USD per share) \| $ / shares	$ 108.72
Granted (in USD per share) \| $ / shares	135.48
Adjustment for performance achievement (in USD per share) \| $ / shares	107.67
Vested/exercised (in USD per share) \| $ / shares	100.30
Forfeited (in USD per share) \| $ / shares	110.95
Ending balance (in USD per share) \| $ / shares	$ 125.25

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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The addition or reduction in the number of reserved shares that could potentially be issued under the option plan attributable to reasons other than grants, exercises, forfeitures, and expirations during the reporting period.

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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