CONSOLIDATED STATEMENTS OF INCOME - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest and dividend income:
Interest and fees on loans	$ 135,159,000	$ 97,480,000	$ 70,289,000
Interest on interest-earning deposits	1,785,000	1,002,000	940,000
Interest on investment securities	2,652,000	2,351,000	1,406,000
Dividend income on FHLB stock	1,079,000	650,000	472,000
Interest on federal funds sold and other	1,050,000	632,000	997,000
Total interest income	141,725,000	102,115,000	74,104,000
Interest expense:
Interest on savings deposits, now and money market accounts	4,886,000	4,408,000	2,382,000
Interest on time deposits	29,347,000	12,548,000	7,891,000
Interest on subordinated debentures and long-term debt	7,698,000	4,083,000	3,629,000
Interest on other borrowed funds	2,930,000	2,606,000	36,000
Total interest expense	44,861,000	23,645,000	13,938,000
Net interest income	96,864,000	78,470,000	60,166,000
Provision (recapture) for credit losses	2,390,000	4,469,000	(1,053,000)
Net interest income after provision (recapture) for credit losses	94,474,000	74,001,000	61,219,000
Noninterest income:
Service charges, fees and other	4,072,000	2,679,000	2,111,000
Gain on sale of loans	9,893,000	7,126,000	9,318,000
Loan servicing fees, net of amortization	3,383,000	850,000	722,000
Recoveries on loans acquired in business combinations	143,000	1,385,000	84,000
Unrealized gain on equity investments	147,000
Increase in cash surrender value of life insurance	775,000	797,000	824,000
Gain on sale of securities	7,000	5,000
(Loss) gain on sale of OREO	(106,000)		142,000
Gain on sale of fixed assets	6,000
Total noninterest income	18,320,000	12,842,000	13,201,000
Noninterest expense:
Salaries and employee benefits	32,909,000	23,254,000	16,821,000
Occupancy and equipment expenses	9,750,000	4,554,000	2,940,000
Data processing	3,699,000	2,323,000	1,622,000
Legal and professional	1,832,000	1,714,000	331,000
Office expenses	1,257,000	890,000	679,000
Marketing and business promotion	1,308,000	1,143,000	837,000
Insurance and regulatory assessments	900,000	951,000	799,000
Core deposit premium	1,501,000	575,000	355,000
OREO expenses	337,000	24,000	28,000
Merger expenses	471,000	1,658,000	37,000
Other expenses	3,509,000	3,551,000	3,174,000
Total noninterest expense	57,473,000	40,637,000	27,623,000
Income before income taxes	55,321,000	46,206,000	46,797,000
Income tax expense	16,112,000	10,101,000	21,269,000
Net income	$ 39,209,000	$ 36,105,000	$ 25,528,000
Net income per share
Basic	$ 1.96	$ 2.11	$ 1.81
Diluted	1.92	2.01	1.68
Cash dividends declared per common share	$ 0.40	$ 0.35	$ 0.38
Weighted-average common shares outstanding
Basic	20,017,306	17,151,222	14,078,281
Diluted	20,393,424	17,967,653	15,238,365