Loans and Allowance for Loan Losses - Allowance Allocation (Details) - USD ($)		Jun. 30, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		$ 61,944,494	$ 58,980,475
Troubled debt restructurings performing as of restructure date		14,200,000	15,000,000
Commercial real estate - mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		16,002,000	13,655,000
Consumer real estate - mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		7,835,000	6,564,000
Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		5,126,000	3,624,000
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		24,235,000	24,743,000
Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		7,549,000	9,520,000
Unallocated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		1,197,000	874,000
Troubled Debt Restructurings
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses	[1]	62,000	21,000
Troubled Debt Restructurings | Commercial real estate - mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses	[1]	1,000	1,000
Troubled Debt Restructurings | Consumer real estate - mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses	[1]	3,000	2,000
Troubled Debt Restructurings | Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses	[1]	0	0
Troubled Debt Restructurings | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses	[1]	58,000	18,000
Troubled Debt Restructurings | Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses	[1]	0	0
Troubled Debt Restructurings | Unallocated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses	[1]	0	0
Accruing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		59,280,000	57,014,000
Accruing | Commercial real estate - mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		15,963,000	13,595,000
Accruing | Consumer real estate - mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		6,891,000	5,874,000
Accruing | Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		5,104,000	3,604,000
Accruing | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		24,005,000	24,648,000
Accruing | Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		7,317,000	9,293,000
Accruing | Unallocated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		0	0
Nonaccruing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		1,405,000	1,071,000
Nonaccruing | Commercial real estate - mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		38,000	59,000
Nonaccruing | Consumer real estate - mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		941,000	688,000
Nonaccruing | Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		22,000	20,000
Nonaccruing | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		172,000	77,000
Nonaccruing | Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		232,000	227,000
Nonaccruing | Unallocated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for Loan Losses		$ 0	$ 0

[1] Troubled debt restructurings of $14.2 million and $15.0 million as of both June 30, 2017 and December 31, 2016, respectively, are classified as impaired loans pursuant to U.S. GAAP; however, these loans continue to accrue interest at contractual rates.