Annual report pursuant to Section 13 and 15(d)

Accumulated Other Comprehensive Income (Details)

v3.8.0.1
Accumulated Other Comprehensive Income (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]      
Beginning Balances $ 339,135 $ 568,512 $ 666,214
Current period other comprehensive income 3,332 (4,956) (1,607)
Ending Balances 296,121 339,135 $ 568,512
Foreign Currency Items      
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]      
Beginning Balances (6,844)    
Current period other comprehensive income 3,332    
Ending Balances $ (3,512) $ (6,844)