CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($)	9 Months Ended
Jan. 31, 2018	Jan. 31, 2017
Common Stock [Member]
Stock Issuance costs	$ 111,000	$ 340,000
Series E Preferred Stock [Member]
Stock Issuance costs	$ 0	$ 58,000

The cash outflow for cost incurred directly with the issuance of an equity security.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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