Note 8 - Leases (Details) - Leased Property Under Capital Leases By Major Classes (USD $) In Thousands, unless otherwise specified	Apr. 30, 2014	Apr. 30, 2013
Capital Leased Assets [Line Items]
Capital Leased assets,gross	$ 16,278	$ 15,486
Less accumulated amortization	5,202	4,900
	11,076	10,586
Real Estate1 [Member]
Capital Leased Assets [Line Items]
Capital Leased assets,gross	13,668	12,874
Equipment [Member]
Capital Leased Assets [Line Items]
Capital Leased assets,gross	$ 2,610	$ 2,612

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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- Details

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- Definition

The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

+ Details

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- Definition

The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45014-112735

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 2)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

+ Details

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