Business Segment and Foreign Operations - Long-lived Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Long-lived Assets from External Customers and Long-Lived Assets [Line Items]
Long-lived tangible assets	$ 94,576	$ 81,606
United States [Member]
Long-lived Assets from External Customers and Long-Lived Assets [Line Items]
Long-lived tangible assets	6,785	5,716
People's Republic of China [Member]
Long-lived Assets from External Customers and Long-Lived Assets [Line Items]
Long-lived tangible assets	82,893	70,619
All Other Countries [Member]
Long-lived Assets from External Customers and Long-Lived Assets [Line Items]
Long-lived tangible assets	$ 4,898	$ 5,271