Note 6 - Stockholders' Equity - Reconciliation of Activity in Stockholders' Equity Accounts (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Balance			$ 19,982,000
Net loss	$ (305,000)	$ (2,080,000)	(707,000)	$ (4,957,000)
Adjustment to net periodic benefit cost	30,000	$ 24,000	81,000	$ 71,000
Balance	19,467,000		19,467,000
Common Stock [Member]
Balance			275,000
Net loss
Dividend payable adjustment due to restricted share forfeitures
Stock-based compensation
Adjustment to net periodic benefit cost
Balance	275,000		275,000
Additional Paid-in Capital [Member]
Balance			16,840,000
Net loss
Dividend payable adjustment due to restricted share forfeitures
Stock-based compensation			(23,000)
Adjustment to net periodic benefit cost
Balance	16,817,000		16,817,000
Retained Earnings [Member]
Balance			5,129,000
Net loss			(707,000)
Dividend payable adjustment due to restricted share forfeitures			134,000
Stock-based compensation
Adjustment to net periodic benefit cost
Balance	4,556,000		4,556,000
AOCI Attributable to Parent [Member]
Balance			(2,262,000)
Net loss
Dividend payable adjustment due to restricted share forfeitures
Stock-based compensation
Adjustment to net periodic benefit cost			81,000
Balance	$ (2,181,000)		$ (2,181,000)