Summary Consolidated Statements Of Operations And Comprehensive Income (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenues:
Products	$ 18,195,000	$ 16,696,000	$ 37,991,000	$ 33,150,000
Preservation services	15,317,000	16,313,000	30,994,000	31,972,000
Other	8,000	179,000	71,000	367,000
Total revenues	33,520,000	33,188,000	69,056,000	65,489,000
Cost of products and preservation services:
Products	3,721,000	2,673,000	7,186,000	5,186,000
Preservation services	8,320,000	9,144,000	17,115,000	17,640,000
Total cost of products and preservation services	12,041,000	11,817,000	24,301,000	22,826,000
Gross margin	21,479,000	21,371,000	44,755,000	42,663,000
Operating expenses:
General, administrative, and marketing	16,932,000	13,871,000	34,909,000	31,841,000
Research and development	1,736,000	1,670,000	3,724,000	3,363,000
Total operating expenses	18,668,000	15,541,000	38,633,000	35,204,000
Operating income	2,811,000	5,830,000	6,122,000	7,459,000
Interest expense	54,000	52,000	104,000	117,000
Interest income		(1,000)	(2,000)	(3,000)
Other expense, net	22,000	174,000	241,000	159,000
Income before income taxes	2,735,000	5,605,000	5,779,000	7,186,000
Income tax expense	950,000	2,271,000	1,802,000	2,861,000
Net income	1,785,000	3,334,000	3,977,000	4,325,000
Income per common share:
Basic	$ 0.06	$ 0.12	$ 0.14	$ 0.16
Diluted	$ 0.06	$ 0.12	$ 0.14	$ 0.15
Dividends declared per share	$ 0.0275		$ 0.0525
Weighted-average common shares outstanding:
Basic	26,856	26,864	26,858	27,022
Diluted	27,369	27,177	27,456	27,362
Net income	1,785,000	3,334,000	3,977,000	4,325,000
Other comprehensive income	54,000	6,000	21,000	8,000
Comprehensive income	$ 1,839,000	$ 3,340,000	$ 3,998,000	$ 4,333,000