Consolidated Statements Of Operations And Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenues:
Products	$ 30,094	$ 30,045	$ 57,490	$ 57,063
Preservation services	17,724	17,038	35,387	33,036
Total revenues	47,818	47,083	92,877	90,099
Cost of products and preservation services:
Products	6,959	7,698	14,976	14,701
Preservation services	7,954	9,084	15,484	17,476
Total cost of products and preservation services	14,913	16,782	30,460	32,177
Gross margin	32,905	30,301	62,417	57,922
Operating expenses:
General, administrative, and marketing	23,389	22,436	46,260	48,710
Research and development	4,728	3,279	8,821	5,888
Total operating expenses	28,117	25,715	55,081	54,598
Gain from sale of business components				(7,915)
Operating income	4,788	4,586	7,336	11,239
Interest expense	834	797	1,635	1,514
Interest income	(55)	(18)	(95)	(30)
Other income, net	(134)	(58)	(91)	(167)
Income before income taxes	4,143	3,865	5,887	9,922
Income tax expense	980	1,518	501	5,034
Net income	$ 3,163	$ 2,347	$ 5,386	$ 4,888
Income per common share:
Basic	$ 0.09	$ 0.07	$ 0.16	$ 0.15
Diluted	$ 0.09	$ 0.07	$ 0.16	$ 0.15
Weighted-average common shares outstanding:
Basic	32,664	32,010	32,552	31,519
Diluted	33,814	32,764	33,739	32,270
Other comprehensive income (loss)	$ 129	$ (332)	$ 365	$ (428)
Comprehensive income	$ 3,292	$ 2,015	$ 5,751	$ 4,460