Income taxes - Operating loss carryovers (Details) - USD ($) $ in Thousands	Mar. 28, 2020	Mar. 30, 2019
Operating loss carryovers
Valuation allowances	$ 2,135	$ 2,181
Foreign and Domestic
Operating loss carryovers
Tax credits	931	1,190
Foreign and State
Operating loss carryovers
Deferred tax assets for net operating loss carryovers	$ 2,279	$ 2,317

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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