Investment securities available for sale (Details Textual) - USD ($) |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2017 |
Sep. 30, 2016 |
Sep. 30, 2017 |
Sep. 30, 2016 |
Dec. 31, 2016 |
|
| Schedule of Available-for-sale Securities [Line Items] | |||||
| Pledged Assets Separately Reported, Securities Pledged for Repurchase Agreements, at Fair Value | $ 1,050,000 | ||||
| Proceeds from Sale of Available-for-sale Securities, Debt | $ 4,000,000 | $ 22,000,000 | |||
| Available-for-sale Securities, Gross Realized Gain (Loss) | $ 0 | $ 15,000 | $ (9,000) | $ 162,000 | |