Supplemental Retirement Plan and Other Postretirement Benefit Obligations (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($) officer	Mar. 31, 2019 USD ($)
Supplemental Employee Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Number of Active Executive Officers under Plan | officer	2
Number of Former Executive Officers under Plan | officer	1
Term of SERP benefits	20 years
Benefits Paid	$ 69	$ 69
Net periodic benefit cost	20	25
Remaining expected SERP accrual in current year	60
Supplemental Life Insurance Benefit
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	$ 23	$ 50