Loans and Allowance for Loan Losses Loans and Allowance for Loan Losses - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of loan portfolio as commercial loan	77.00%		77.00%
Risk rated loans	$ 1,000,000		$ 1,000,000
Impaired receivable increase	26,741,000	$ 37,004,000	26,670,000	$ 36,629,000
Cash payments received on nonaccrual loans	16,000	41,000	65,000	88,000
Nonaccrual loans	1,000,000	396,000	1,500,000	676,000
Troubled debt restructurings performing as of restructure date	$ 14,200,000		$ 14,200,000		$ 15,000,000
Percentage of credit exposure to risk based capital	25.00%		25.00%
Loans and other extensions of credit granted to directors, executive officers, and their related entities	$ 25,800,000		$ 25,800,000		22,600,000
Amount drawn from loans and other extensions of credit granted	17,200,000		17,200,000		14,800,000
Commercial loans held-for-sale	11,400,000		11,400,000
Mortgage loans held-for-sale	90,275,468		90,275,468		$ 47,710,120
Loans sold			261,981,394	198,239,000
Gain on mortgage loans sold, net	$ 4,667,537	$ 4,221,301	$ 8,822,489	$ 7,788,852