Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Other Current Liabilities [Abstract]
Acquisition Obligations	$ 6,664	$ 77,594
Customer Advances, Current	24,983	2,980
Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Share Value, Amount	0	4,925
Other Sundry Liabilities, Current	0	180
Other current liabilities	$ 31,647	$ 85,679