Income Taxes - Income tax expense (Details) - USD ($)		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes.
Federal corporate income tax rate	21.00%	21.00%	21.00%	34.00%
Additional income tax expense due to write off of deferred tax asset				$ 208,000
Income Taxes from Continuing Operations:
Deferred		$ 254,000	$ 54,000
Income Tax Expense		$ 254,000	$ 54,000