Shareholders' Equity - Reclassification Out of Accumulated Other Comprehensive Loss (Details) - Affected Line Item in the Statement Where Net Loss is Presented [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)
Total reclassifications for the period	$ (2,200)
Amortization of Net Actuarial Loss [Member] | Other Income (Expense) [Member]
Total reclassifications for the period	(2,900)
Cumulative Translation Adjustment [Member] | Other Income (Expense) [Member]
Total reclassifications for the period	$ 700