Income Taxes - Carryforwards (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Components of deferred tax assets and liabilities
Deferred Tax assets related to net unrealized losses on held-to-maturity securities transferred from available-for-sale securities		$ 2,400,000
Alternative minimum tax credit
Net operating loss carryforward
Alternative minimum tax credit that can be carried forward	$ 2,100,000
2024
Net operating loss carryforward
Net operating loss carryforward	15,000
2025
Net operating loss carryforward
Net operating loss carryforward	96,500,000
2026
Net operating loss carryforward
Net operating loss carryforward	317,000
2027
Net operating loss carryforward
Net operating loss carryforward	52.000
2028
Net operating loss carryforward
Net operating loss carryforward	177,000
Federal
Net operating loss carryforward
Net operating loss carryforward	55,300,000
Federal | 2030
Net operating loss carryforward
Net operating loss carryforward	31,400,000
Federal | 2031
Net operating loss carryforward
Net operating loss carryforward	8,600,000
Federal | 2032
Net operating loss carryforward
Net operating loss carryforward	15,300,000
State
Net operating loss carryforward
Net operating loss carryforward	99,900,000
State | 2021
Net operating loss carryforward
Net operating loss carryforward	$ 2,800,000