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Amount of allowance for credit loss on financing receivable, classified as current.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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Amount, before allowance for credit loss, of financing receivable, classified as noncurrent.

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities.

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Assets Held for Sale (Details) - USD ($)	May 21, 2019	Apr. 27, 2018	Apr. 30, 2020
FEI-Asia [Member]
Assets Held for Sale (Details) [Line Items]
Proceeds from Sales of Business, Affiliate and Productive Assets	$ 130,000
Disposal Group, Including Discontinued Operation, Revenue	85,000
Gain (Loss) on Disposition of Business	$ (1,000,000)
Gillam Frequency Electronics Inc [Member]
Assets Held for Sale (Details) [Line Items]
Proceeds from Divestiture of Businesses		$ 1,000,000
Financing Receivable, before Allowance for Credit Loss, Noncurrent		$ 1,000,000
Financing Receivable, Allowance for Credit Loss, Current			$ 1,000,000