Annual report pursuant to Section 13 and 15(d)

Employees' Benefit Plans (Details Textual)

v3.8.0.1
Employees' Benefit Plans (Details Textual) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]    
Eligibility Of Employees Employees are eligible to participate in the Employees Savings and Profit Sharing Plan and Trust on the next January 1 or July 1 following the completion of one year of employment, attaining age 18, and completion of 1,000 hours of service.  
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay 8.00% 9.00%
Defined Contribution Plan, Cost Recognized $ 796 $ 843
Deferred Compensation Liability, Current and Noncurrent 211 200
Deferred Compensation Arrangement with Individual, Compensation Expense 6 13
Deferred Costs 68 72
Deferred Fee Liability $ 1,300 $ 1,400
Trust for Benefit of Employees [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Description of Defined Contribution Pension and Other Postretirement Plans Participants also become 100% vested in the employer contributions and accrued earnings in their account upon their death, approved disability, or attainment of age 65 while employed at the Bank.  
Two Years Of Service [Member] | Trust for Benefit of Employees [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Defined Benefit Plan, Funded Percentage 40.00%  
Three Years Of Service [Member] | Trust for Benefit of Employees [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Defined Benefit Plan, Funded Percentage 60.00%  
Four Years Of Service [Member] | Trust for Benefit of Employees [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Defined Benefit Plan, Funded Percentage 80.00%  
Five Years Of Service [Member] | Trust for Benefit of Employees [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Defined Benefit Plan, Funded Percentage 100.00%  
Maximum [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Defined Benefit Plan Employees Pre Tax Contributions 50.00%  
Minimum [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Defined Benefit Plan Employees Pre Tax Contributions 1.00%