Summary of Significant Accounting Policies - Allowance for Loans - (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Federal Home Loan Bank ("FHLB") stock	$ 3,216,000	$ 3,216,000	$ 2,545,000
Loans Held-for-sale [Abstract]
Proceeds from Sale of Loans Held-for-sale		4,178,000
Net gains		$ 165,000
Allowance for Loan and Lease Losses [Abstract]
Rolling average period used to determine historical loss rates		3 years
Company and Bank-Owned Life Insurance
Proceeds from Life Insurance Policies		$ 748,000	1,420,000
Income from company owned life insurance		1,166,000	497,000
Advertising Cost [Abstract]
Advertising Expense		$ 243,000	190,000
Benefit Plans [Abstract]
Highest consecutive years of employee compensation used to compute benefit		3 years
Years of employment used in benefit computation		10 years
Employer matching contribution to employee's contributions between 1% and 5% (in hundredths)		100.00%
Employee contribution matched by employer, lower range (in hundredths)		1.00%
Employer matching contribution to employees contribution that are within the specified limit (in hundredths)		5.00%
Maximum annual contribution per employee		$ 2,500
Employer contribution to plan		135,000	134,000
Stock Compensation [Abstract]
Compensation expense			64,000
Income Taxes [Abstract]
Unrecognized Tax Benefits	0	0
Deferred tax valuation allowance	26,600,000	26,600,000	30,600,000
Increase in valuation allowance		(4,297,000)	(8,564,000)
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount		4,000,000
Increase associated with equity investments	308,000	$ 308,000
Net income (loss) per common share [Abstract]
Rate class B shares may be converted to class A shares		1.15 to 1
Restrictions on Cash and Amounts Due From Banks [Abstract]
Average balances on hand with the Federal Reserve Bank	100,000	$ 100,000
Other investments, notice period to redeem funds		60 days
Former employee
Company and Bank-Owned Life Insurance
Proceeds from Life Insurance Policies	748,000
Income from company owned life insurance	$ 273,000
Minimum [Member]
Derivatives and Hedging Instruments [Abstract]
Percentage of designated hedge risk		80.00%
Maximum [Member]
Derivatives and Hedging Instruments [Abstract]
Percentage of designated hedge risk		125.00%
Restricted stock
Stock Compensation [Abstract]
Compensation expense			$ 78,000
Employee Stock Option
Stock Compensation [Abstract]
Compensation expense		$ 85,000