Supplemental Retirement Plan and Other Postretirement Benefit Obligations (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($) officer	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) officer	Jun. 30, 2018 USD ($)
Supplemental Employee Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Number of Active Executive Officers under Plan | officer	2		2
Number of Former Executive Officers under Plan | officer	1		1
Term of SERP benefits			20 years
Benefits Paid	$ 69	$ 69	$ 138	$ 138
SERP expenses	108	56	219	112
Remaining expected SERP accrual in current year	209		209
Supplemental Life Insurance Benefit
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	$ 49	$ 44	$ 99	$ 89