FHLB Advances and Other Borrowings (Schedule of Issuance of Subordinated Debentures) (Details) - USD ($)				12 Months Ended
	Jul. 15, 2005	May 06, 2005	Mar. 26, 2003	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Percentage over variable rate				2.875%
ACB Trust I
Debt Instrument [Line Items]
Date of Issuance		May 06, 2005
Issuance Amount		$ 5,155,000
Carrying Amount at December 31, 2017				$ 3,553,000
Variable Rate		90 day LIBOR + 2.15%
Rate as of December 31				3.84%	3.15%
Maturity Date		May 31, 2035
ACB Trust I | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Percentage over variable rate		2.15%
ACB Trust II
Debt Instrument [Line Items]
Date of Issuance	Jul. 15, 2005
Issuance Amount	$ 3,093,000
Carrying Amount at December 31, 2017				$ 2,071,000
Variable Rate	90 day LIBOR + 1.85%
Rate as of December 31				3.30%	2.77%
Maturity Date	Jul. 31, 2035
ACB Trust II | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Percentage over variable rate	1.85%
RIVR Statutory Trust 1
Debt Instrument [Line Items]
Date of Issuance			Mar. 26, 2003
Issuance Amount			$ 7,217,000
Carrying Amount at December 31, 2017				$ 5,607,000
Variable Rate			3-Month LIBOR + 3.15%
Rate as of December 31				4.82%	4.15%
Maturity Date			Mar. 31, 2033
RIVR Statutory Trust 1 | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Percentage over variable rate			3.15%