Shareholders' equity and regulatory matters (Details) - USD ($)
$ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
Mar. 27, 2015 |
| Total capital (to risk-weighted assets), Amount [Abstract] |
|
|
|
| For Capital Adequacy Purposes |
|
$ 13,707
|
|
| To be Well Capitalized Amount |
|
$ 15,231
|
|
| Total capital (to risk-weighted assets), Ratio [Abstract] |
|
|
|
| Actual Ratio (in percentage) |
|
12.85%
|
|
| To be Well Capitalized (in percentage) |
|
6.50%
|
|
| Leverage ratio (Tier 1 capital to average assets), Amount [Abstract] |
|
|
|
| To be Well Capitalized Amount |
|
$ 20,970
|
|
| Leverage ratio (Tier 1 capital to average assets), Ratio [Abstract] |
|
|
|
| For Capital Adequacy Purposes (in percentage) |
4.00%
|
|
9.33%
|
| To be Well Capitalized (in percentage) |
|
5.00%
|
|
| Common equity (Tier 1 risk based capital to risk weighted assets), Ratio [Abstract] |
|
|
|
| Actual Ratio (in percentage) |
31.00%
|
|
|
| For Capital Adequacy Purposes (in percentage) |
7.00%
|
|
|
| Subsidiaries [Member] |
|
|
|
| Total capital (to risk-weighted assets), Amount [Abstract] |
|
|
|
| Actual Amount |
$ 49,225
|
$ 42,695
|
|
| For Capital Adequacy Purposes |
25,693
|
24,369
|
|
| To be Well Capitalized Amount |
$ 42,117
|
$ 30,461
|
|
| Total capital (to risk-weighted assets), Ratio [Abstract] |
|
|
|
| Actual Ratio (in percentage) |
15.33%
|
14.02%
|
|
| For Capital Adequacy Purposes (in percentage) |
8.00%
|
8.00%
|
|
| To be Well Capitalized (in percentage) |
10.00%
|
10.00%
|
|
| Tier 1 capital (to risk-capital to average assets), Amount [Abstract] |
|
|
|
| Actual Amount |
$ 45,852
|
$ 39,133
|
|
| For Capital Adequacy Purposes |
12,847
|
12,184
|
|
| To be Well Capitalized Amount |
$ 19,270
|
$ 18,277
|
|
| Tier 1 capital (to risk-capital to average assets), Ratio [Abstract] |
|
|
|
| Actual Ratio (in percentage) |
14.28%
|
12.85%
|
|
| For Capital Adequacy Purposes (in percentage) |
4.00%
|
4.00%
|
|
| To be Well Capitalized (in percentage) |
6.00%
|
6.00%
|
|
| Leverage ratio (Tier 1 capital to average assets), Amount [Abstract] |
|
|
|
| Actual Amount |
$ 45,852
|
$ 39,133
|
|
| For Capital Adequacy Purposes |
17,523
|
$ 16,776
|
|
| To be Well Capitalized Amount |
$ 21,903
|
|
|
| Leverage ratio (Tier 1 capital to average assets), Ratio [Abstract] |
|
|
|
| Actual Ratio (in percentage) |
10.47%
|
9.33%
|
|
| For Capital Adequacy Purposes (in percentage) |
4.00%
|
4.00%
|
|
| To be Well Capitalized (in percentage) |
5.00%
|
|
|
| Common equity (Tier 1 risk based capital to risk weighted assets), Amount [Abstract] |
|
|
|
| Actual Amount |
$ 45,852
|
$ 39,133
|
|
| For Capital Adequacy Purposes |
14,452
|
|
|
| To be Well Capitalized Amount |
$ 20,876
|
|
|
| Common equity (Tier 1 risk based capital to risk weighted assets), Ratio [Abstract] |
|
|
|
| Actual Ratio (in percentage) |
14.28%
|
|
|
| For Capital Adequacy Purposes (in percentage) |
4.50%
|
4.50%
|
|
| To be Well Capitalized (in percentage) |
6.50%
|
|
|