Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 34,620	$ 37,303
Receivables, less allowance for doubtful accounts of $515 at March 31, 2014 and $512 at December 31, 2013	18,150	17,032
Inventories	12,177	11,048
Prepaid expenses	2,062	690
Refundable income taxes	949	1,537
Deferred income taxes	1,248	1,222
Total current assets	69,206	68,832
Property, plant, and equipment	65,951	64,574
Less accumulated depreciation and amortization	(40,079)	(39,067)
Net property, plant, and equipment	25,872	25,507
Goodwill	7,322	7,322
Intangible assets, net	1,227	1,346
Other assets	2,064	2,013
Total assets	105,691	105,020
Current liabilities:
Accounts payable	4,648	3,081
Accrued expenses	5,717	8,265
Current installments of long-term debt	980	976
Total current liabilities	11,345	12,322
Long-term debt, excluding current installments	2,620	2,867
Deferred income taxes	2,341	2,436
Retirement and other liabilities	1,525	1,805
Total liabilities	17,831	19,430
Commitments and contingencies
Stockholders' equity:
Preferred stock, $.01 par value. Authorized 1,000,000 shares; zero shares issued or outstanding
Common stock, $.01 par value. Authorized 20,000,000 shares; issued and outstanding 6,996,838 at March 31, 2014 and 6,900,683 at December 31, 2013	70	69
Additional paid-in capital	20,498	20,291
Retained earnings	67,292	65,230
Total stockholders' equity	87,860	85,590
Total liabilities and stockholders' equity	$ 105,691	$ 105,020