Earnings Per Share - Reconciliation of Basic and Diluted EPS Calculations (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 28, 2020	Mar. 30, 2019
Earnings Per Share [Abstract]
Net income	$ 9,742	$ 17,429
Weighted average shares outstanding for basic EPS (shares)	80,129	78,205
Effect of dilutive securities:
Stock options (shares)	2,020	3,221
Restricted stock (shares)	93	40
Weighted average shares outstanding for diluted EPS	82,242	81,466
Basic EPS (in usd per share)	$ 0.12	$ 0.22
Diluted EPS (in usd per share)	$ 0.12	$ 0.21
Options and RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive options, RSUs outstanding excluded from EPS (shares)	394	356

Incremental Common Shares Attributable to Dilutive Effect of Vesting of Restricted Stock

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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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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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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