XML 112 R93.htm IDEA: XBRL DOCUMENT v3.8.0.1
Employee Benefit Plans (Schedule of Reconciliation of Prepaid Pension Costs) (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Pension Plan [Member]      
Prepaid pension cost (liability) as of beginning of fiscal year $ 5,965 $ 5,007  
Net periodic pension cost for fiscal year 1,117 958 $ 1,483
Actual employer contributions
Benefits paid (2,080) (2,114) (2,051)
Prepaid pension cost (liability) as of end of fiscal year 7,082 5,965 5,007
SERP [Member]      
Prepaid pension cost (liability) as of beginning of fiscal year (6,754) (6,802)  
Net periodic pension cost for fiscal year (311) (309) (328)
Benefits paid (370) (357)  
Prepaid pension cost (liability) as of end of fiscal year $ (6,695) $ (6,754) $ (6,802)