Geographic Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 46,901	$ 61,902
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	41,344	56,021
Americas, excluding U.S.
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	700	579
Europe, Middle East, India, Africa
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	3,216	3,643
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 1,641	$ 1,659