Percentage of foreign federal statutory tax rate applicable to pretax income (loss).

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Refers to term of tax year holidays.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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The amount of income taxes from which a reporting entity is exempt or for which it will receive a reduction in income taxes as a result of the income tax holiday granted by the taxing jurisdiction.

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Per share amount effect of the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions.

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The date on which the special tax status will terminate.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of unrecognized tax benefits.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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INCOME TAXES (Details) - USD ($) $ / shares in Units, $ in Thousands	2 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Dec. 31, 2017	Apr. 28, 2019	Apr. 29, 2018	Apr. 28, 2019	Apr. 29, 2018	Oct. 29, 2017	Oct. 31, 2018
Effective Income and Statutory Tax Rate [Abstract]
Effective tax rate		25.00%	18.80%	20.90%	6.50%
U.S. statutory rate	35.00%	21.00%	23.40%	21.00%	23.40%
Unrecognized Tax Benefits [Abstract]
Unrecognized tax benefits		$ 800		$ 800			$ 1,900
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued [Abstract]
Accrued interest and penalties related to unrecognized tax benefits		100		$ 100			100
Taiwan Agency of the Ministry of Finance [Member]
Foreign Tax [Abstract]
Foreign statutory rate				20.00%		17.00%
Foreign income tax expense (benefit)				$ (200)
Income Tax Holiday [Abstract]
Term of tax year holidays				5 years
Income tax holiday termination date				December 31, 2019
Dollar effect of income tax holiday		$ 300	$ 700	$ 1,100	$ 800
Per share effect of income tax holiday (in dollars per share)			$ 0.01	$ 0.01	$ 0.01
Federal Alternate Minimum [Member]
Tax Credit Carryforward [Abstract]
Change in valuation allowance				$ 3,900
ASU 2016-16 [Member]
Adoption of New Accounting Standard [Abstract]
Cumulative effect of adoption of new accounting principle							$ (1,130)