Summary of Business and Significant Accounting Policies (Principles of Consolidation and Reclassification) (Details) $ in Millions	12 Months Ended
Jan. 31, 2020 USD ($)
Accounting Policies [Abstract]
Reclassification of prior year sales allowances to cost of goods sold	$ 1.9

The amount of a reclassification adjustment made to prior period financial statement amounts.

No definition available.

Name:	us-gaap_PriorPeriodReclassificationAdjustment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration