For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Business And Summary Of Significant Accounting Policies (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 30, 2019	Apr. 30, 2018	Jan. 31, 2019
Accounting Policies [Abstract]
Accounts receivable sold	$ 800.0		$ 1,100.0
Discount fees on sale of accounts receivable	$ 3.7	$ 2.7
Apple
Concentration Risk [Line Items]
Concentration Risk, Percentage	13.00%	14.00%
Cisco Systems, Inc.
Concentration Risk [Line Items]
Concentration Risk, Percentage	11.00%	11.00%
HP, Inc.
Concentration Risk [Line Items]
Concentration Risk, Percentage	10.00%	12.00%