Income Taxes - Schedule of Provision for Federal Income Taxes (Detail) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended |
|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2016 |
|
| Current | ||
| Federal | $ 247 | |
| Total current tax expense | 247 | |
| Deferred | ||
| Total income tax expense | $ 247 | $ 247 |