Pension Plan (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Pension Plan [Abstract]
Highest consecutive years of employee compensation used to compute benefit			3 years
Years of employment used in benefit computation			10 years
Net Pension Cost [Abstract]
Service cost	$ 13	$ 11	$ 39	$ 35
Interest cost	137	143	413	428
Amortization of actuarial loss	50	43	150	129
Net periodic benefit cost	200	$ 197	602	$ 592
Unfunded pension plan obligations	15,100		15,100		$ 15,200
Cash surrender value of life insurance policies	$ 4,600		$ 4,600		$ 4,700