| | | December 31, 2017 | | December 31, 2016 | | December 31, 2015 | | |||
| Expenses: | | | | | | | | | | |
| Compensation costs paid to directors | | | 884 | | | 880 | | | 949 | |
| Compensation costs paid to executives | | | 2,370 | | | 4,055 | | | 4,601 | |