Retirement Plans and Other Post Retirement Benefits - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Other Post Retirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions for next fiscal year		$ 89
Defined benefit plan, contributions by employer	$ 28
Defined benefit plan, benefits paid	28
Nonqualified Plan [Member] | Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions for next fiscal year		$ 159
Defined benefit plan, contributions by employer	40
Defined benefit plan, benefits paid	$ 664