Investment Securities (Amortized Cost and Estimated Fair Values of Investment Securities) (Details) - USD ($) $ in Thousands		Dec. 15, 2016	Sep. 30, 2017	Dec. 31, 2016
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale securities, Amortized Cost			$ 213,400	$ 165,462
Available-for-sale securities, Gross Unrealized Gains			724	319
Available-for-sale securities, Gross Unrealized Losses			734	1,879
Available-for-sale securities, Estimated Fair Value			213,390	163,902
Held-to-maturity securities, Amortized Cost			6,241	6,704
Held-to-maturity securities, Gross Unrealized Gains			210	102
Held-to-maturity securities, Estimated Fair Value			6,451	6,806
Equity [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale securities, Amortized Cost			662	652
Available-for-sale securities, Gross Unrealized Losses				12
Available-for-sale securities, Estimated Fair Value			662	640
Other Equity Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale securities, Amortized Cost	[1]		3,000	3,000
Available-for-sale securities, Gross Unrealized Gains	[1]		107
Available-for-sale securities, Estimated Fair Value	[1]		3,107	3,000
Floating interest rate		6.50%
U.S. Government Agencies [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale securities, Amortized Cost			52,093	34,320
Available-for-sale securities, Gross Unrealized Gains			64	56
Available-for-sale securities, Gross Unrealized Losses			154	58
Available-for-sale securities, Estimated Fair Value			52,003	34,318
Held-to-maturity securities, Amortized Cost			1,837	2,089
Held-to-maturity securities, Gross Unrealized Gains			42	26
Held-to-maturity securities, Estimated Fair Value			1,879	2,115
States and Political Subdivisions [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Held-to-maturity securities, Amortized Cost			1,404	1,615
Held-to-maturity securities, Gross Unrealized Gains			61	76
Held-to-maturity securities, Estimated Fair Value			1,465	1,691
Mortgage-backed [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale securities, Amortized Cost			160,645	130,490
Available-for-sale securities, Gross Unrealized Gains			660	263
Available-for-sale securities, Gross Unrealized Losses			580	1,809
Available-for-sale securities, Estimated Fair Value			$ 160,725	$ 128,944

[1] On December 15, 2016, the Company bought $3.0 million in subordinated notes with a fixed to floating rate of 6.5% from a local regional bank which it intends to hold to maturity of December 30, 2026.