Investment Securities (Amortized Cost and Estimated Fair Values of Investment Securities) (Details) - USD ($) $ in Thousands		9 Months Ended
Dec. 15, 2016	Sep. 30, 2018	Dec. 31, 2017
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale securities, Amortized Cost			$ 198,670
Available-for-sale securities, Gross Unrealized Gains			180
Available-for-sale securities, Gross Unrealized Losses			1,895
Available-for-sale securities, Estimated Fair Value		$ 168,324	196,955
Held-to-maturity securities, Amortized Cost		6,037	6,247
Held-to-maturity securities, Gross Unrealized Gains		17	144
Held-to-maturity securities, Gross Unrealized Losses		71
Held-to-maturity securities, Estimated Fair Value		5,983	6,391
Equity securities, at fair value		649
Fair value adjustment		(20)
Equity [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale securities, Amortized Cost			666
Available-for-sale securities, Gross Unrealized Losses			8
Available-for-sale securities, Estimated Fair Value			658
Debt Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale securities, Amortized Cost		173,218
Available-for-sale securities, Gross Unrealized Gains		128
Available-for-sale securities, Gross Unrealized Losses		5,671
Available-for-sale securities, Estimated Fair Value		167,675
U.S. Government Agencies [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale securities, Amortized Cost		42,411	45,806
Available-for-sale securities, Gross Unrealized Gains		2	23
Available-for-sale securities, Gross Unrealized Losses		867	497
Available-for-sale securities, Estimated Fair Value		41,546	45,332
Held-to-maturity securities, Amortized Cost		1,635	1,844
Held-to-maturity securities, Gross Unrealized Gains			21
Held-to-maturity securities, Gross Unrealized Losses		50
Held-to-maturity securities, Estimated Fair Value		1,585	1,865
States and Political Subdivisions [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Held-to-maturity securities, Amortized Cost		1,402	1,403
Held-to-maturity securities, Gross Unrealized Gains		17	47
Held-to-maturity securities, Estimated Fair Value		1,419	1,450
Other Debt Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Held-to-maturity securities, Amortized Cost	$ 3,000	3,000	3,000
Held-to-maturity securities, Gross Unrealized Gains			76
Held-to-maturity securities, Gross Unrealized Losses		21
Held-to-maturity securities, Estimated Fair Value		2,979	3,076
Floating interest rate	6.50%
Mortgage-backed [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale securities, Amortized Cost		130,807	152,198
Available-for-sale securities, Gross Unrealized Gains		126	157
Available-for-sale securities, Gross Unrealized Losses		4,804	1,390
Available-for-sale securities, Estimated Fair Value		$ 126,129	$ 150,965

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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