Business Segment and Geographic Region Information - Revenue and Long-Lived Assets (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
Revenue and long-lived assets by geographic region
Revenue	$ 69,358	$ 65,650	$ 64,451	$ 67,521	$ 70,458	$ 79,317	$ 78,437	$ 73,283	$ 266,980	$ 301,495	$ 203,051
Long-Lived Assets	52,523				42,063				52,523	42,063	40,300
United States.
Revenue and long-lived assets by geographic region
Revenue									191,261	226,890	126,255
Long-Lived Assets	52,006				41,729				52,006	41,729	40,001
Europe
Revenue and long-lived assets by geographic region
Revenue									25,436	24,209	29,140
Asia Pacific
Revenue and long-lived assets by geographic region
Revenue									50,283	50,396	47,656
Long-Lived Assets	$ 517				$ 334				517	334	299
International | Revenue | Geographic concentration risk
Revenue and long-lived assets by geographic region
Revenue									$ 213,800	$ 256,500	$ 162,400
Percentage of revenue									80.00%	85.10%	80.00%