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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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The after-tax amount of interest recognized in the period associated with any convertible debt.

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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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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities, and addition from assumption of issuance of common shares for dilutive potential common shares; of income (loss) available to common shareholders.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Net Income per Share - Schedule of reconciliation of earnings per share (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 27, 2019	Sep. 27, 2019	Jun. 28, 2019	Mar. 29, 2019	Dec. 28, 2018	Sep. 28, 2018	Jun. 29, 2018	Mar. 30, 2018	Dec. 27, 2019	Dec. 28, 2018	Dec. 29, 2017
Net Income (Loss) Available to Common Stockholders, Basic [Abstract]
Net income	$ 10,888	$ 4,425	$ 7,746	$ 1,134	$ 8,882	$ 4,157	$ 6,819	$ 544	$ 24,193	$ 20,402	$ 14,366
Net Income (Loss) Available to Common Stockholders, Diluted [Abstract]
Interest on convertible notes, net of tax									207	362	536
Adjusted net income									$ 24,400	$ 20,764	$ 14,902
Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract]
Weighted average basic common shares outstanding (in shares)									29,532,342	28,703,265	26,118,482
Dilutive effect of stock options and unvested common shares (in shares)									211,050	270,520	68,670
Dilutive effect of convertible notes (in shares)									329,946	705,134	1,237,374
Weighted average diluted common shares outstanding (in shares)									30,073,338	29,678,919	27,424,526