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The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (e)

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Amount of (increase) decrease reasonably possible in the estimated lower bound of the unrecognized tax benefit for a tax position taken or expected to be taken.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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-Paragraph 15A

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Note 8 - Unrecognized Tax Benefits (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Apr. 30, 2014
Note 8 - Unrecognized Tax Benefits (Details) [Line Items]
Unrecognized Tax Benefits	$ 9,759		$ 9,244
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	6,466
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	183		402
Income Tax Examination, Penalties and Interest Expense	219	94
Significant (Increase) Decrease in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	$ 2,549
Earliest Tax Year [Member] \| Domestic Tax Authority [Member]
Note 8 - Unrecognized Tax Benefits (Details) [Line Items]
Open Tax Year	2010
Earliest Tax Year [Member] \| State and Local Jurisdiction [Member]
Note 8 - Unrecognized Tax Benefits (Details) [Line Items]
Open Tax Year	2009