Quarterly report pursuant to Section 13 or 15(d)

Derivative Financial Instruments (Narrative) (Details)

v3.10.0.1
Derivative Financial Instruments (Narrative) (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Sales $ 45,881 $ 30,680 $ 99,148 $ 72,236
Unrealized Gains (Losses) on Cash Flow Hedges [Member]        
Maximum net exposure to company     680  
Reclassification Out Of Accumulated Other Comprehensive Income [Member] | Unrealized Gains (Losses) on Cash Flow Hedges [Member]        
Sales $ (5) $ 90 $ (330) $ 386