Retirement Plans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Retirement Benefits [Abstract]
Automatic Annual Contribution Employees Hired Before January 1, 2009 Benefit Reduction Under Certain Amendments Minimum, percent	5.00%
Automatic Annual Contribution Employees Hired Before January 1, 2009 Due Benefit Reduction Under Certain Amendments Maximum, percent	7.00%
Employer's matching contribution to 401(k) of employees hired on or after January 1, 2009, percent	50.00%
Maximum annual contribution per employee, percent	3.00%
Funding and administrative costs of noncontributory defined benefit retirement plan and 401(k) plan [Abstract]
401(k) plan	$ 143	$ 110
Qualified noncontributory defined benefit retirement plan [Member]
Funding and administrative costs of noncontributory defined benefit retirement plan and 401(k) plan [Abstract]
Qualified noncontributory defined benefit retirement plan	256	261
Components of net periodic pension cost [Abstract]
Service cost	0	0
Interest cost	18	17
Amortization of unrecognized net loss	0	4
Net periodic pension cost	18	$ 21
Recognized in accumulated other comprehensive income [Abstract]
Net actuarial (gain) loss	0		$ 88
Past service cost	0		0
Total recognized, net of tax	$ 0		$ 88