v3.5.0.1

Fair Value of Financial Assets and Liabilities - Summary of Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Apr. 30, 2016	Apr. 30, 2015
Cash and Cash Equivalents [Line Items]
Total cash and cash equivalents	$ 43,963	$ 54,041
Municipal debt securities
Cash and Cash Equivalents [Line Items]
Total cash and cash equivalents	0	102
Corporate debt securities
Cash and Cash Equivalents [Line Items]
Total cash and cash equivalents	0	256
Demand deposit accounts
Cash and Cash Equivalents [Line Items]
Total cash and cash equivalents	38,692	49,977
Money market funds
Cash and Cash Equivalents [Line Items]
Total cash and cash equivalents	922	2,831
Commercial paper
Cash and Cash Equivalents [Line Items]
Total cash and cash equivalents	$ 4,349	$ 875

X

- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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X

- Definition

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.

+ References

No definition available.

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