CONDENSED CONSOLIDATED STATEMENTS OF INCOME AND RETAINED EARNINGS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
CONDENSED CONSOLIDATED STATEMENTS OF INCOME AND RETAINED EARNINGS
Net sales	$ 38,627	$ 37,647	$ 112,617	$ 114,596
Costs and expenses:
Cost of sales (exclusive of depreciation, depletion and amortization)	31,426	29,609	91,232	89,899
Depreciation, depletion and amortization	617	607	1,932	1,897
Selling and administrative	5,361	5,527	17,210	17,406
Charges related to cessation of mining an aggregates deposit		632		632
Gain on disposition of property and equipment	(95)	(89)	(119)	(281)
Total costs and expenses	37,309	36,286	110,255	109,553
Operating income	1,318	1,361	2,362	5,043
Interest income	18	285	50	293
Interest expense	(98)	(83)	(272)	(299)
Other income, net	28	16	44	41
Income before income taxes	1,266	1,579	2,184	5,078
Provision for income taxes	431	537	743	1,727
Net income	835	1,042	1,441	3,351
Retained earnings, beginning of period	65,775	63,792	65,169	61,483
Retained earnings, end of period	$ 66,610	$ 64,834	$ 66,610	$ 64,834
Basic and diluted income per share	$ 0.50	$ 0.62	$ 0.86	$ 2.01
Average shares outstanding (in shares)	1,682	1,672	1,679	1,669