Operating Segments and Geographic Information (Operations by Geographic Area) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Long-Lived Assets	$ 682,123	$ 684,652
United States
Segment Reporting Information [Line Items]
Long-Lived Assets	469,234	476,560
China
Segment Reporting Information [Line Items]
Long-Lived Assets	55,078	58,205
Germany
Segment Reporting Information [Line Items]
Long-Lived Assets	120,869	113,412
Other
Segment Reporting Information [Line Items]
Long-Lived Assets	$ 36,942	$ 36,475