Note 10 - Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2016
Dec. 31, 2015
Assets    
Allowance for loan losses $ 3,285 $ 3,625
Deferred directors’ fees 236 242
Postretirement benefit obligations 5,825 5,665
Other real estate owned 1,303 1,968
Self-funded insurance 232 230
Paid time off 815 756
Depreciation 1,630 1,440
Intangibles 1,878 2,432
Unrealized loss on available for sale investment securities, net 1,811
Other 239 307
Total deferred tax assets 17,254 16,665
Unrealized gains on available for sale investment securities, net 1,734
Prepaid expenses 153 306
Federal Home Loan Bank stock dividends 1,035 1,035
Deferred loan fees 846 806
Other 52 65
Total deferred tax liabilities 2,086 3,946
Net deferred tax asset $ 15,168 $ 12,719