Summary of Significant Accounting Policies (Details)	1 Months Ended	12 Months Ended
	Jul. 31, 2011 trust	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jan. 01, 2019 USD ($)
Interest-bearing Deposits in Other Banks [Abstract]
Maturity period of interest bearing deposits in other banks		1 year
Derivative Loan Commitments [Abstract]
Period of time between issuance and sale of loan commitment, minimum		30 days
Period of time between issuance and sale of loan commitment, maximum		60 days
Loans [Abstract]
Period to discontinued interest accrual on delinquent loans		90 days
Past due period when loans are charged off		120 days
Troubled Debt Restructurings [Abstract]
Loans classified as TDR		$ 1,058,000	$ 1,090,000
Income Taxes [Abstract]
Unrecognized tax benefits		0	0
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of stranded tax effects from tax rate change				$ (545,000)
Liabilities		2,158,292,000	1,640,324,000
Advertising and Marketing Costs [Abstract]
Advertising and marketing costs		$ 473,000	$ 365,000	352,000
Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives		3 years
Finite-Lived Intangible Assets [Line Items]
Amortization period of intangible		8 years
Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives		39 years
Finite-Lived Intangible Assets [Line Items]
Amortization period of intangible		10 years
Software
Property, Plant and Equipment [Line Items]
Estimated useful lives		3 years
MidCarolina
Finite-Lived Intangible Assets [Line Items]
Amortization period of intangible	108 months
MidCarolina | Delaware
Business Acquisition [Line Items]
Number of unconsolidated statutory trusts | trust	2
Accounting Standard Update 2018-02 | New Accounting Principles, Early Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of stranded tax effects from tax rate change				$ 545,000
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Liabilities					$ 4,400,000