Geographic Information - Long Lived Assets Attributed to Geographic Area (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	$ 91,129	$ 130,745	$ 107,076
United States
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	45,225	61,557	54,703
Americas-Other
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	10,889	10,702	13,834
Germany
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	26,295	30,154	26,611
Europe-Other
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	4,984	24,935	9,124
Japan
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	1,423	1,039	558
Asia-Other
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	$ 2,313	$ 2,358	$ 2,246