Total Assets by Reportable Segments (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
ASSETS
Total segment assets	$ 172,760	$ 123,514	$ 116,754
Cash and cash equivalents	100,057	68,108	59,959	$ 51,146
Prepaid income taxes and income taxes receivable	4,387	2,058	2,510
Prepaid expenses and other current assets	10,675	5,570	5,989
Property, plant and equipment, net	61,718	35,421	40,550
Deferred tax assets	7,052	8,593	7,885
Other assets	4,018	12,502	12,673
Intangible assets, net	155,048	61,743	66,269
Goodwill	210,988	108,128	103,456
Total assets	$ 726,703	$ 425,637	$ 416,045