Credit Quality Indicators (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	$ 975,866	$ 895,561
Pass
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	956,981	873,901
Special Mention
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	6,318	11,415
Substandard
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	12,567	10,245
Originated Loans
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	826,785	723,220
Originated Loans | Pass
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	816,954	711,466
Originated Loans | Special Mention
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	4,825	6,459
Originated Loans | Substandard
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	5,006	5,295
Originated Loans | Commercial real estate | Commercial real estate, Owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	152,714	139,926
Originated Loans | Commercial real estate | Commercial real estate, Non-owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	240,304	198,588
Originated Loans | Commercial real estate | Commercial farmland
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	94,882	70,443
Originated Loans | Commercial real estate | Commercial real estate, Other
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	91,673	88,703
Originated Loans | Commercial real estate | Pass | Commercial real estate, Owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	150,728	137,913
Originated Loans | Commercial real estate | Pass | Commercial real estate, Non-owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	239,817	198,043
Originated Loans | Commercial real estate | Pass | Commercial farmland
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	94,808	70,354
Originated Loans | Commercial real estate | Pass | Commercial real estate, Other
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	91,417	88,421
Originated Loans | Commercial real estate | Special Mention | Commercial real estate, Owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	971	442
Originated Loans | Commercial real estate | Special Mention | Commercial real estate, Non-owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	377	419
Originated Loans | Commercial real estate | Special Mention | Commercial farmland
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	0	44
Originated Loans | Commercial real estate | Special Mention | Commercial real estate, Other
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	0	36
Originated Loans | Commercial real estate | Substandard | Commercial real estate, Owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	1,015	1,571
Originated Loans | Commercial real estate | Substandard | Commercial real estate, Non-owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	110	126
Originated Loans | Commercial real estate | Substandard | Commercial farmland
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	74	45
Originated Loans | Commercial real estate | Substandard | Commercial real estate, Other
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	256	246
Originated Loans | Commercial | Commercial and industrial
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	213,166	192,879
Originated Loans | Commercial | Commercial, Agricultural
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	34,046	32,681
Originated Loans | Commercial | Pass | Commercial and industrial
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	206,823	184,444
Originated Loans | Commercial | Pass | Commercial, Agricultural
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	33,361	32,291
Originated Loans | Commercial | Special Mention | Commercial and industrial
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	3,464	5,326
Originated Loans | Commercial | Special Mention | Commercial, Agricultural
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	13	192
Originated Loans | Commercial | Substandard | Commercial and industrial
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	2,879	3,109
Originated Loans | Commercial | Substandard | Commercial, Agricultural
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	672	198
Acquired Loans
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	149,081	172,341
Acquired Loans | Pass
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	140,027	162,435
Acquired Loans | Special Mention
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	1,493	4,956
Acquired Loans | Substandard
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	7,561	4,950
Acquired Loans | Commercial real estate | Commercial real estate, Owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	47,500	53,051
Acquired Loans | Commercial real estate | Commercial real estate, Non-owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	18,121	20,258
Acquired Loans | Commercial real estate | Commercial farmland
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	42,256	47,755
Acquired Loans | Commercial real estate | Commercial real estate, Other
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	10,722	11,976
Acquired Loans | Commercial real estate | Pass | Commercial real estate, Owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	46,279	51,133
Acquired Loans | Commercial real estate | Pass | Commercial real estate, Non-owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	17,832	19,823
Acquired Loans | Commercial real estate | Pass | Commercial farmland
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	38,041	43,694
Acquired Loans | Commercial real estate | Pass | Commercial real estate, Other
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	10,060	11,299
Acquired Loans | Commercial real estate | Special Mention | Commercial real estate, Owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	443	466
Acquired Loans | Commercial real estate | Special Mention | Commercial real estate, Non-owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	60	63
Acquired Loans | Commercial real estate | Special Mention | Commercial farmland
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	449	3,304
Acquired Loans | Commercial real estate | Special Mention | Commercial real estate, Other
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	0	567
Acquired Loans | Commercial real estate | Substandard | Commercial real estate, Owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	778	1,452
Acquired Loans | Commercial real estate | Substandard | Commercial real estate, Non-owner occupied
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	229	372
Acquired Loans | Commercial real estate | Substandard | Commercial farmland
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	3,766	757
Acquired Loans | Commercial real estate | Substandard | Commercial real estate, Other
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	662	110
Acquired Loans | Commercial | Commercial and industrial
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	19,634	27,094
Acquired Loans | Commercial | Commercial, Agricultural
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	10,848	12,207
Acquired Loans | Commercial | Pass | Commercial and industrial
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	17,910	25,286
Acquired Loans | Commercial | Pass | Commercial, Agricultural
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	9,905	11,200
Acquired Loans | Commercial | Special Mention | Commercial and industrial
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	195	2
Acquired Loans | Commercial | Special Mention | Commercial, Agricultural
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	346	554
Acquired Loans | Commercial | Substandard | Commercial and industrial
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	1,529	1,806
Acquired Loans | Commercial | Substandard | Commercial, Agricultural
Financing Receivable Recorded Investment [Line Items]
Total risk category of loans by class of loans	$ 597	$ 453