Segment and Significant Concentrations - Segment Revenue by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 144,780	$ 132,637
Long-lived assets	143,969		$ 127,639
North America
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	82,390	82,305
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	79,700	77,000
Long-lived assets	125,102		108,210
Non-US
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	18,867		$ 19,429
International Countries [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 62,390	$ 50,332