Pension Plan (Details) - Components of net periodic pension cost - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Pension Plan (Details) - Components of net periodic pension cost [Line Items]
Interest cost	$ 125,000	$ 114,000	$ 376,000	$ 340,000
Expected return on plan assets	(172,000)	(203,000)	(517,000)	(609,000)
Amortization of net actuarial loss	65,000	56,000	196,000	168,000
Net periodic pension expense (benefit)	$ 18,000	$ (33,000)	$ 55,000	$ (101,000)