XML 81 R68.htm IDEA: XBRL DOCUMENT v3.8.0.1
Employee Benefit Plans (Net Periodic Pension Cost) (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Retirement Benefits [Abstract]      
Service cost $ 603 $ 452 $ 240
Interest cost on projected benefit obligation 2,773 2,878 3,394
Expected return on plan assets (5,300) (5,189) (5,697)
Amortization of loss 2,835 2,780 3,233
Net periodic pension cost $ 911 $ 921 $ 1,170