Segment Reporting and Foreign Operations - Operating Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net Sales	$ 157,715	$ 156,975	$ 151,071	$ 138,077	$ 138,404	$ 136,086	$ 138,082	$ 129,577	$ 603,838	$ 542,149	$ 509,689
Operating expenses									230,149	198,238	185,056
Operating income (loss)									34,876	37,543	40,166
Total other expense - net									(9,490)	(6,343)	(8,594)
Income tax expense	2,116	(978)	2,572	1,555	145	1,842	3,122	2,289	5,265	7,398	8,598
NET INCOME	$ 7,507	$ 973	$ 7,290	$ 4,351	$ 6,409	$ 4,818	$ 7,401	$ 5,174	20,121	23,802	22,974
Cardiovascular Segment
Segment Reporting Information [Line Items]
Net Sales									580,248	520,915	491,706
Operating expenses									218,659	187,492	175,152
Operating income (loss)									30,120	34,052	38,601
Endoscopy Segment
Segment Reporting Information [Line Items]
Net Sales									23,590	21,234	17,983
Operating expenses									11,490	10,746	9,904
Operating income (loss)									$ 4,756	$ 3,491	$ 1,565