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Business Combinations (Details Textual) - USD ($) $ / shares in Units, $ in Thousands					1 Months Ended	12 Months Ended
	Aug. 15, 2017	Jun. 01, 2016	Oct. 01, 2015	Jun. 19, 2015	Aug. 11, 2017	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill						$ 38,201	$ 37,164
Monitor Bancorp, Inc.
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	Aug. 15, 2017
Shares of stock issued for acquisition	465,787
Fair value of total consideration transferred	$ 7,512
Maximum shares exchanged for stock	85.00%
Maximum shares exchanged for cash	15.00%
Cash consideration per share	$ 769.38
Multiplier used to calculate per share cash consideration	1.25
Period of trading days considered for volume weighted average closing price					20 days
Volume weighted average closing price per share of common shares	$ 14.04
Final stock exchange ratio	54.80
Goodwill	$ 1,037
Monitor Bancorp, Inc. | Core Deposits
Business Acquisition [Line Items]
Fair value of other intangible assets	$ 673
Bowers Insurance Agency, Inc.
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition						Jun. 01, 2016
Shares of stock issued for acquisition		123,280
Fair value of total consideration transferred		$ 3,155
Goodwill		1,849
Fair value of other intangible assets		1,630
Contingent future payments		1,200
Contingent consideration		$ 880				$ 316
Contingent consideration future payment liability						200
Reduction to acquisition related costs						364
Bowers Insurance Agency, Inc. | Earnout Payment
Business Acquisition [Line Items]
Contingent consideration						$ 564
Tri-State 1st Banc Incorporation
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Oct. 01, 2015
Shares of stock issued for acquisition			1,296,517
Fair value of total consideration transferred			$ 14,300
Cash consideration per share			$ 14.20
Goodwill			$ 3,000
Shares shareholders are entitled to elect to receive per shares			174.70%
Business Acquisition Shares Being Exchanged for Stock			75.00%
Business Acquisition Shares Being Exchanged for Cash			25.00%
Tri-State 1st Banc Incorporation | Series A Preferred Stock
Business Acquisition [Line Items]
Cash consideration per share			$ 13.60
Tri-State 1st Banc Incorporation | Core Deposits
Business Acquisition [Line Items]
Fair value of other intangible assets			$ 1,200
National Bancshares Corporation
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition				Jun. 19, 2015
Shares of stock issued for acquisition				7,262,955
Fair value of total consideration transferred				$ 74,800
Maximum shares exchanged for stock				80.00%
Maximum shares exchanged for cash				20.00%
Cash consideration per share				$ 32.15
Goodwill				$ 26,700
Shares shareholders are entitled to elect to receive per shares				403.40%
National Bancshares Corporation | Core Deposits
Business Acquisition [Line Items]
Fair value of other intangible assets				$ 4,400

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