Business, Basis of Presentation and Summary of Significant Accounting Policies - Business (Details)	Jan. 31, 2018 location state
Business
Number of branches through which products are distributed \| location	210
Number of states in which products are distributed \| state	42

The number of states the entity operates in as of the balance sheet date.

No definition available.

Name:	us-gaap_NumberOfStatesInWhichEntityOperates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant