XML 87 R74.htm IDEA: XBRL DOCUMENT v3.8.0.1
Employee Benefit Plans (Amounts Recognized in the Balance Sheets) (Details) - USD ($)
$ in Thousands
Dec. 31, 2017
Dec. 31, 2016
Pension Benefits [Member]    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Noncurrent liabilities $ (5,763) $ (6,821)
Net amount recognized at December 31 (5,763) (6,821)
Postretirement Benefit Plan [Member]    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Current liabilities (400) (403)
Noncurrent liabilities (5,556) (5,769)
Net amount recognized at December 31 $ (5,956) $ (6,172)