Pension And Postretirement Benefit Plans (Details) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
---|---|---|---|---|
Jun. 30, 2017
USD ($)
|
Jun. 30, 2016
USD ($)
|
Jun. 30, 2017
USD ($)
employee
|
Jun. 30, 2016
USD ($)
|
|
Defined Benefit Plan Disclosure [Line Items] | ||||
Retired employees receiving health care and life insurance benefits | employee | 9 | |||
Post retirement benefits, age eligibility requirement | 65 years | |||
Post retirement benefits, service eligibility requirement | 15 years | |||
Postretirement Benefits [Member] | ||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Net periodic benefit cost | $ | $ (1) | $ 0 | $ (2) | $ (1) |