XML 99 R76.htm IDEA: XBRL DOCUMENT v3.10.0.1
Pension and Other Postretirement Benefits (Components of Net Periodic Postretirement Benefit Cost) (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Ultimate healthcare trend rates 3.80%    
Other Postretirement Benefits      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Service cost $ 18 $ 17 $ 22
Interest cost 233 269 272
Amortization of unrecognized prior service cost 44 44 44
Loss amortization (2) 132 146 134
Net periodic pension cost $ 427 $ 476 $ 472
Discount rate 4.10% 3.40% 3.80%
Annual rate of increase in the per capita cost of: Medical costs before age 65 7.00% 7.30% 7.50%
Annual rate of increase in the per capita cost of: Medical costs after age 65 5.00% 6.30% 6.50%
Annual rate of increase in the per capita cost of: Prescription drug costs 9.50% 10.50% 10.50%