Segment Reporting (Summary of Revenues and Long-Lived Assets by Geographic Region) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Revenue	$ 56,670	$ 59,366
Long-Lived Assets	157,389		$ 152,944
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Revenue	55,930	58,538
Long-Lived Assets	106,352		104,110
CHINA
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	36,034		35,085
FRANCE
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Revenue	740	$ 828
Long-Lived Assets	14,914		13,659
UNITED KINGDOM
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	$ 89		$ 90