LONG-TERM DEBT (Details)		12 Months Ended
	Apr. 29, 2016 USD ($) ft²	Dec. 31, 2016 USD ($)	Apr. 01, 2016 USD ($)	Dec. 31, 2015 USD ($)
Remaining principal payments
Less: Current portion		$ 127,303
Long-term portion		3,077,457
Loan
Financing agreement
Monthly payments including interest	$ 18,000
Interest rate	2.14%
Deferred debt issuance costs, gross	$ 139,000
Loan’s effective interest rate	2.77%
Debt service coverage ratio	1.25
Remaining principal payments
2017		140,000
2018		143,000
2019		146,000
2020		149,000
2021		152,000
Thereafter		2,605,000
Total Principal		3,335,000
Less: Unamortized debt issuance costs		131,000
Less: Current portion		127,000
Long-term portion		3,077,000
Debt Issuance Costs
Amortization of debt costs		9,000
Deferred debt issuance costs, noncurrent, net		118,000
Deferred debt issuance costs, current, net		13,000
Annual expected amortization expense over the next five years		$ 12,000
Remaining amortization period		5 years
Loan | Building
Financing agreement
Area of building | ft²	27,300
Line Of Credit.
Debt Issuance Costs
Maximum borrowings		$ 2,050,000
Outstanding borrowings		$ 0		$ 0
Line Of Credit. | 30-day LIBOR
Debt Issuance Costs
Line of credit basis spread (as a percent)		1.80%
Duluth Economic Development Authority
Financing agreement
Bonds issued to the Bank			$ 3,415,000