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Summary of Significant Accounting Policies - Property, Equipment and Capitalized Software Costs - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 26, 2020	Jun. 28, 2019	Jun. 26, 2020	Jun. 28, 2019	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Capitalized software developed for commercial use	$ 13,592		$ 13,592		$ 17,384
Depreciation and amortization expense			1,641	$ 1,365
Capitalized Software [Member]
Property Plant And Equipment [Line Items]
Capitalized computer software, additions	300		600
Capitalized software developed for commercial use	2,700	$ 2,000	2,700	2,000
Depreciation and amortization expense	100	100	200	300
Capitalized software costs, accumulated amortization	1,100	$ 1,000	$ 1,100	1,000
Capitalized Software [Member] \| Maximum [Member]
Property Plant And Equipment [Line Items]
Capitalized computer software, additions				$ 100
Property, equipment and capitalized software, useful life			5 years
Capitalized Software [Member] \| Minimum [Member]
Property Plant And Equipment [Line Items]
Property, equipment and capitalized software, useful life			3 years
Building \| Buffalo, NY [Member]
Property Plant And Equipment [Line Items]
Book value of building	$ 1,600		$ 1,600
Proceeds from sale of building			2,500
Gain on sale of building			$ 800