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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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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.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. 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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2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details Narrative) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Oct. 31, 2017	Jul. 31, 2017	Oct. 31, 2017	Oct. 31, 2016	Apr. 30, 2017	Apr. 30, 2016
Cash and cash equivalents	$ 27,727,000		$ 27,727,000	$ 49,055,000	$ 46,799,000	$ 61,412,000
Restricted cash pledged as collateral	$ 1,150,000		1,150,000		$ 1,150,000
Asset impairment charges			$ 0	$ 0
Accounts Receivable [Member] \| Seven or Fewer [Member]
Concentration percentage			95.00%		93.00%
Sales Revenue, Net [Member] \| Two Customers [Member]
Concentration percentage	83.00%		81.00%
Shelf Registration [Member]
Amount remaining under shelf registration statements	$ 67,674,000		$ 67,674,000
Common Stock [Member]
Gross proceeds from issuance of equity		$ 4,304,000