Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Pension Benefits
Components of net periodic benefit costs:
Interest cost	$ 109	$ 104	$ 328	$ 314
Expected return on plan assets	(195)	(147)	(586)	(440)
Amortization of net loss	19	29	58	84
Settlement charge	0	176	0	176
Net periodic benefit/cost	(67)	162	(200)	134
Postretirement Benefits
Components of net periodic benefit costs:
Interest cost	1	0	3	2
Amortization of net loss	(2)	(1)	(4)	(4)
Amortization of prior service cost	0		(1)
Net periodic benefit/cost	$ (1)	$ (1)	$ (2)	$ (2)
Postretirement Benefits | Employees Hired before January 1, 2003
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Benefit based on highest average salary for number of consecutive years			5 years
Number of years for consecutive years calculation			10 years
Postretirement Benefits | Employees Hired on or after January 1, 2003
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Percent of annual salary to calculate benefit			2.00%
Retirement prior to January 1, 1993 [Member]
Components of net periodic benefit costs:
Percent of healthcare costs paid	100.00%		100.00%