Accumulated Other Comprehensive Loss (Reclassifications from Accumulated Other Comprehensive Loss) (Details) $ in Millions	3 Months Ended
Apr. 30, 2022 USD ($)
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income tax benefit	$ (1)
Total, net of tax	1
Pension Benefits [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Pension benefits	$ 2

Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for net period benefit cost (credit) of defined benefit plan.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount, after tax, of reclassification adjustment from accumulated other comprehensive (income) loss for net periodic benefit cost (credit) of defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e689-108580

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Amount of tax (expense) benefit for reclassification adjustment from accumulated other comprehensive (income) loss of defined benefit plan.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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