Segment Reporting - Net Sales by Product and Services (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
Product net sales									$ 168,510	$ 241,609	$ 159,220
Services net sales									140,190	132,501	101,786
Total net sales	$ 67,380	$ 81,202	$ 73,725	$ 86,393	$ 93,567	$ 107,697	$ 95,536	$ 77,310	$ 308,700	$ 374,110	$ 261,006