Pension Plan (Details) - Components of net periodic pension cost - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Pension Plan (Details) - Components of net periodic pension cost [Line Items]
Interest cost	$ 96,000	$ 126,000	$ 193,000	$ 251,000
Expected return on plan assets	(204,000)	(173,000)	(407,000)	(345,000)
Amortization of net actuarial loss	71,000	66,000	141,000	131,000
Net periodic pension (benefit) expense	$ (37,000)	$ 19,000	$ (73,000)	$ 37,000