Organization, Use of Estimates and Basis of Presentation - Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Jul. 31, 2018	Apr. 30, 2018	Jul. 31, 2017	Apr. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash	$ 1,016	$ 856
Cash Equivalents	0	0
Cash and cash equivalents	1,016	856
Restricted cash	150	150
Total cash, cash equivalents, and restricted cash shown in the statement of cash flows	$ 1,166	$ 1,006	$ 580	$ 3,445

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Amount 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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.

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Amount of 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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