Net income per common share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Jun. 27, 2020	Jun. 29, 2019
Numerator:
Net income (loss)	$ (16,670)	$ (4,099)
Denominator:
Weighted-average common shares - basic and diluted (in shares)	48,389,205	48,231,148
Net loss per common share - basic and diluted	$ (0.34)	$ (0.08)
Stock options outstanding
Antidilutive securities not included:
Antidilutive securities	2,545,383	2,497,573
Nonvested restricted stock awards
Antidilutive securities not included:
Antidilutive securities	674,176	197,687

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

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