Loans Payable and Long-Term Debt (Narrative) (Details)	3 Months Ended
Jul. 31, 2015
Debt Instrument [Line Items]
Ratio of total liabilities to tangible net worth	0.7
Ratio of cash flow to fixed charges	3.20
Maximum [Member]
Debt Instrument [Line Items]
Ratio of total liabilities to tangible net worth	1.4

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.

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration