Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016	Dec. 22, 2017	Dec. 31, 2015	Jan. 03, 2015
Income Taxes [Line Items]
Refundable AMT and adjustment to indefinite-lived deferred tax liability					$ 90,000
Corporate federal income tax rate		34.00%	34.00%	34.00%
Accrued interest and penalty		$ 0
Ending balance of unrecognized tax benefits		1,105,000	$ 1,029,000	$ 937,000			$ 861,000
Unrecognized tax benefits recognition impact on income tax rate		$ 0
Earliest Tax Year
Income Taxes [Line Items]
Open Tax Year		2010
Latest Tax Year
Income Taxes [Line Items]
Open Tax Year		2016
Scenario Forecast
Income Taxes [Line Items]
Corporate federal income tax rate	21.00%
Federal
Income Taxes [Line Items]
Net operating loss		$ 21,500,000
Net operating loss expiration year		2032
Research credit						$ 1,800,000
State
Income Taxes [Line Items]
Net operating loss		$ 16,700,000
Net operating loss expiration year		2020
Research credit						$ 2,600,000