Pension and Other Post-Retirement Plans - Summary of Information Pertaining to Activity in Plan (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Change in benefit obligation:
Defined benefit plan, unrecognized net actuarial loss			$ 344,000
Defined Benefit Plan [Member]
Change in plan assets:
Fair value of plan assets at beginning of year		$ 3,197,000
Settlement payments		(3,644,000)
Benefits paid		(107,000)
Employer contributions		554,000
Fair value of plan assets at end of year			3,197,000
Change in benefit obligation:
Benefit obligation at beginning of year		3,552,000
Interest cost		71,000
Defined benefit plan, unrecognized net actuarial loss		128,000
Settlement payments		(3,644,000)
Benefits paid		(107,000)
Benefit obligation at end of year			3,552,000
Supplemental Retirement Plan [Member]
Change in plan assets:
Benefits paid	$ (371,000)	(201,000)
Employer contributions	371,000	201,000
Change in benefit obligation:
Benefit obligation at beginning of year	2,105,000	1,862,000
Service cost	12,000	11,000
Interest cost	65,000	72,000
Defined benefit plan, unrecognized net actuarial loss	25,000	361,000
Benefits paid	(371,000)	(201,000)
Benefit obligation at end of year	1,836,000	2,105,000	$ 1,862,000
Funded status and accrued pension cost at year end	(1,836,000)	(2,105,000)
Accumulated benefit obligation at year end	$ 1,836,000	$ 2,105,000