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Stock-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 23, 2020	Sep. 25, 2019	Sep. 23, 2020	Sep. 25, 2019	Dec. 25, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, options outstanding (shares)	1,035,866		1,035,866		2,077,570
Common stock, options vested (shares)			689,166
Common stock, options unvested (shares)	346,700		346,700
Unvested restricted shares outstanding (shares)	769,107		769,107		588,008
Stock-based compensation expense	$ 900	$ 700	$ 2,170	$ 1,797
Premium Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, options outstanding (shares)	303,786		303,786
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, recognition period			2 years 2 months 23 days
Unrecognized compensation expense	$ 1,100		$ 1,100
Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, recognition period			3 years 3 days
Unvested restricted shares outstanding (shares)	684,971		684,971
Unrecognized compensation expense	$ 7,300		$ 7,300
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, recognition period			2 years 7 months 13 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, recognition period			1 year 7 months 13 days
Unrecognized compensation expense	$ 400		$ 400
Unvested restricted shares outstanding (shares)	48,078		48,078