Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest income
Loans	$ 501,336	$ 428,374	$ 344,472
Securities
Taxable	29,875	23,948	18,531
Tax-exempt	5,477	6,456	9,433
Other	5,892	3,076	2,314
Total interest income	542,580	461,854	374,750
Interest expense
Deposits	81,995	49,760	24,620
Borrowings	16,928	15,569	13,233
Total interest expense	98,923	65,329	37,853
Net interest income	443,657	396,525	336,897
Provision for loan losses	7,050	6,810	7,550
Net interest income after provision for loan losses	436,607	389,715	329,347
Noninterest income
Service charges on deposit accounts	35,972	34,660	33,224
Fees and commissions	19,430	23,868	21,934
Insurance commissions	8,919	8,590	8,361
Wealth management revenue	14,433	13,540	11,884
Mortgage banking income	57,896	50,142	43,415
Net gains (losses) on sales of securities	348	(16)	148
BOLI income	6,109	4,644	4,353
Other	10,147	8,533	8,821
Total noninterest income	153,254	143,961	132,140
Noninterest expense
Salaries and employee benefits	250,784	214,294	184,540
Data processing	19,679	18,627	16,474
Net occupancy and equipment	49,553	42,111	37,756
Other real estate owned	2,013	1,892	2,470
Professional fees	10,166	8,753	7,150
Advertising and public relations	11,607	9,464	8,248
Intangible amortization	8,105	7,179	6,530
Communications	8,858	8,318	7,578
Merger and conversion related expenses	279	14,246	10,378
Extinguishment of debt	54	0	205
Other	13,076	20,145	20,289
Total noninterest expense	374,174	345,029	301,618
Income before income taxes	215,687	188,647	159,869
Income taxes	48,091	41,727	67,681
Net income	$ 167,596	$ 146,920	$ 92,188
Basic earnings per share (usd per share)	$ 2.89	$ 2.80	$ 1.97
Diluted earnings per share (usd per share)	2.88	2.79	1.96
Cash dividends per common share (usd per share)	$ 0.87	$ 0.80	$ 0.73