Shareholders' Equity (Details) $ in Millions	3 Months Ended	6 Months Ended
Jul. 31, 2021 USD ($) shares	Jul. 31, 2021 USD ($) shares
Equity [Abstract]
Repurchase of stock (in shares) \| shares	7,006,326	9,156,898
Repurchase of stock	$ 700.0	$ 950.0
Repurchase of stock, shares not settled (in shares)	2.5	2.5
Remaining repurchase authorization	$ 1,450.0	$ 1,450.0

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	debit
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