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Number of non-vested options outstanding.

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Stock-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2021	Sep. 23, 2020	Sep. 29, 2021	Sep. 23, 2020	Dec. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, options outstanding (shares)	1,112,730		1,112,730		1,030,866
Common stock, options vested (shares)			698,329
Common stock, options unvested (shares)	414,401		414,401
Options to purchase common stock granted (shares)			256,172
Aggregate intrinsic value of options outstanding	$ 6,104		$ 6,104
Expected volatility			46.90%
Risk-free interest rate			1.10%
Expected life			6 years 3 months
Granted (shares)			182,059
Unvested restricted shares outstanding (shares)	628,103		628,103		742,404
Stock-based compensation expense	$ 1,000	$ 900	$ 2,936	$ 2,170
Premium Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, options outstanding (shares)	212,196		212,196
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 2,200		$ 2,200
Unrecognized compensation expense, recognition period			3 years 10 days
Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, recognition period			2 years 7 months 28 days
Unvested restricted shares outstanding (shares)	568,006		568,006
Unrecognized compensation expense	$ 6,600		$ 6,600
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, recognition period			1 year 7 months 9 days
Unvested restricted shares outstanding (shares)	36,058		36,058
Unrecognized compensation expense	$ 100		$ 100
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 200		$ 200
Unrecognized compensation expense, recognition period			7 months 9 days
Unvested restricted shares outstanding (shares)	24,039		24,039