Amount paid for monthly capital lease obligations.

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Working Capital

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Amounts to be paid by lessee to lessor for maintenance, insurance, and tax expenses related to the leased asset.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

+ References

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The percentage points added to the reference rate to compute the variable rate on the lessee's capital lease.

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No definition available.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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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.

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No definition available.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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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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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Amount of unrecognized tax benefits.

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Summary of Significant Accounting Policies - Narrative (Details) - USD ($)	12 Months Ended
	Apr. 30, 2019	Apr. 30, 2018	May 01, 2019	Jul. 31, 2018	Oct. 30, 2017	Apr. 30, 2017	Nov. 30, 2014
Property, Plant and Equipment [Line Items]
Restricted cash	$ 0	$ 150,000
Net income (loss)	128,000	(1,476,000)
Accumulated deficit	70,698,000	70,826,000
Working capital	(103,000)
Cash, cash equivalents, restricted cash and restricted cash equivalents	3,237,000	1,006,000				$ 3,445,000
Maximum borrowing capacity					$ 1,500,000.0
Unrecognized tax benefits	$ 151,000	$ 151,000				$ 121,000
Operating lease, liability			$ 4,100,000
Operating lease, right-of-use asset			$ 3,200,000
Minimum
Property, Plant and Equipment [Line Items]
Useful life	3 years
Maximum
Property, Plant and Equipment [Line Items]
Useful life	7 years
November 2014 - Laboratory Equipment Lease
Property, Plant and Equipment [Line Items]
Capital leases, future minimum payments, executory costs							$ 149,000
Capital leases monthly payments							$ 3,000
Capital leases, future minimum payments, present value of net minimum payments	$ 16,000
Capital leases of lessee, contingent rentals, basis spread on variable rate	5.00%
July 2018 - Laboratory Equipment Lease
Property, Plant and Equipment [Line Items]
Capital leases, future minimum payments, executory costs				$ 266,000
Capital leases monthly payments				$ 11,000
Capital leases, future minimum payments, present value of net minimum payments	$ 0