Shareholders' Equity (Rollforward of Activity by Award Type) (Details) shares in Thousands	12 Months Ended
Jan. 31, 2021 $ / shares shares
Restricted Stock [Member]
Shares
Beginning balance (in shares) \| shares	23,261
Granted (in shares) \| shares	7,472
Adjustment for performance achievement (in shares) \| shares	0
Vested/exercised (in shares) \| shares	(7,798)
Forfeited (in shares) \| shares	(3,035)
Ending balance (in shares) \| shares	19,900
Weighted-Average Grant-Date Fair Value Per Share
Beginning balance (in USD per share) \| $ / shares	$ 79.51
Granted (in USD per share) \| $ / shares	114.51
Adjustment for performance achievement (in USD per share) \| $ / shares	0
Vested/exercised (in USD per share) \| $ / shares	76.11
Forfeited (in USD per share) \| $ / shares	92.20
Ending balance (in USD per share) \| $ / shares	$ 92.13
Restricted Stock And Performance Share Awards [Member]
Shares
Beginning balance (in shares) \| shares	6,045
Granted (in shares) \| shares	2,867
Adjustment for performance achievement (in shares) \| shares	576
Vested/exercised (in shares) \| shares	(3,075)
Forfeited (in shares) \| shares	(1,000)
Ending balance (in shares) \| shares	5,413
Weighted-Average Grant-Date Fair Value Per Share
Beginning balance (in USD per share) \| $ / shares	$ 93.04
Granted (in USD per share) \| $ / shares	120.47
Adjustment for performance achievement (in USD per share) \| $ / shares	86.46
Vested/exercised (in USD per share) \| $ / shares	88.88
Forfeited (in USD per share) \| $ / shares	96.36
Ending balance (in USD per share) \| $ / shares	$ 108.72

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
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-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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Weighted average price at which grantees could acquire or could have acquired the underlying shares with respect to any other type of change in shares reserved for issuance.

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

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