Operating Segments and Related Information (Details 5) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting, Asset Reconciling Item [Line Items]
Long-lived assets	$ 1,401,806	$ 1,409,806
United States
Segment Reporting, Asset Reconciling Item [Line Items]
Long-lived assets	797,816	676,007
Europe [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Long-lived assets	343,208	673,767
Other Geographic Region [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Long-lived assets	$ 260,782	$ 60,032