Summary of Significant Accounting Policies (Narrative) (Details)	Apr. 30, 2016 stores
Number of states in which entity operates	45
Minimum [Member]
Number of Stores	870

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