Loans and Allowance for Loan Losses - Loan Summary (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 2,404,057		$ 1,897,392
Less: Allowance for loan losses	(18,817)	$ (16,254)	(10,243)	$ (9,792)	$ (9,097)	$ (8,275)
Loans, net	2,385,240		1,887,149
Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	34,083		26,987
Less: Allowance for loan losses	0		(156)
Loans, net	34,083		26,831
All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	2,369,974		1,870,405
Less: Allowance for loan losses	(18,817)		(10,087)
Loans, net	2,351,157		1,860,318
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,030,651		905,306
Less: Allowance for loan losses	(7,729)	(6,595)	(4,508)	(4,260)	(4,102)	(3,639)
Commercial Real Estate [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	16,469		15,255
Less: Allowance for loan losses	0		(17)
Commercial Real Estate [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,014,182		890,051
Less: Allowance for loan losses	(7,729)		(4,491)
Consumer Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	440,310		417,482
Less: Allowance for loan losses	(3,444)	(3,313)	(2,576)	(2,270)	(2,189)	(1,789)
Consumer Real Estate [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	10,801		6,541
Less: Allowance for loan losses	0		(74)
Consumer Real Estate [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	429,509		410,941
Less: Allowance for loan losses	(3,444)		(2,502)
Construction and Land Development [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	275,172		227,626
Less: Allowance for loan losses	(2,060)	(1,795)	(1,127)	(1,043)	(946)	(795)
Construction and Land Development [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	6,409		4,458
Less: Allowance for loan losses	0		0
Construction and Land Development [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	268,763		223,168
Less: Allowance for loan losses	(2,060)		(1,127)
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	644,498		337,075
Less: Allowance for loan losses	(5,463)	(4,443)	(1,957)	(2,148)	(1,746)	(1,746)
Commercial and Industrial [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	317		407
Less: Allowance for loan losses	0		(59)
Commercial and Industrial [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	644,181		336,668
Less: Allowance for loan losses	(5,463)		(1,898)
Consumer and Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	13,426		9,903
Less: Allowance for loan losses	(121)	$ (108)	(75)	$ (71)	$ (114)	$ (306)
Consumer and Other [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	87		326
Less: Allowance for loan losses	0		(6)
Consumer and Other [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	13,339		9,577
Less: Allowance for loan losses	$ (121)		$ (69)