CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities:
Net income	$ 13,203	$ 10,457	$ 9,118
Depreciation and amortization	3,673	3,698	3,536
Deferred income taxes	(1,775)	(114)	125
Provision for inventory reserves	65	161	233
Other, net	116	169	125
Change in assets and liabilities:
Accounts receivable, net	(115)	(1,596)	(46)
Inventories, net	(473)	(37)	1,532
Accounts payable and accrued liabilities	(962)	153	(1,036)
Accounts with affiliates	(971)	970	37
Other, net	(178)	3	(148)
Net cash provided by operating activities	12,583	13,864	13,476
Cash flows from investing activities:
Capital expenditures	(2,796)	(3,175)	(4,218)
Note receivable from affiliate:
Collections	41,300	9,200
Advances	(52,100)	(36,600)
Net cash used in investing activities	(13,596)	(30,575)	(4,218)
Cash flows from financing activities -
Dividends paid	(2,485)	(2,483)	(2,481)
Net cash used in financing activities	(2,485)	(2,483)	(2,481)
Net increase (decrease)	(3,498)	(19,194)	6,777
Balance at beginning of year	33,153	52,347	45,570
Balance at end of year	29,655	33,153	52,347
Supplemental disclosures -
Cash paid for income taxes	$ 6,709	$ 4,646	$ 4,743