Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest income
Loans	$ 344,472	$ 302,314	$ 236,262
Securities
Taxable	18,531	16,551	17,026
Tax-exempt	9,433	9,814	9,520
Other	2,314	459	215
Total interest income	374,750	329,138	263,023
Interest expense
Deposits	24,620	17,856	13,715
Borrowings	13,233	10,291	7,950
Total interest expense	37,853	28,147	21,665
Net interest income	336,897	300,991	241,358
Provision for loan losses	7,550	7,530	4,750
Net interest income after provision for loan losses	329,347	293,461	236,608
Noninterest income
Service charges on deposit accounts	33,224	31,875	29,269
Fees and commissions	21,934	18,814	15,761
Insurance commissions	8,361	8,508	8,423
Wealth management revenue	11,884	11,652	9,808
Mortgage banking income	43,415	49,443	35,815
Net gains on sales of securities	148	1,186	96
BOLI income	4,353	4,635	3,612
Other	8,821	11,302	5,486
Total noninterest income	132,140	137,415	108,270
Noninterest expense
Salaries and employee benefits	184,540	172,448	145,111
Data processing	16,474	17,723	14,251
Net occupancy and equipment	37,756	34,394	26,987
Other real estate owned	2,470	5,696	3,045
Professional fees	7,150	7,970	4,422
Advertising and public relations	8,248	7,080	6,112
Intangible amortization	6,530	6,747	6,069
Communications	7,578	8,329	7,278
Merger and conversion related expenses	10,378	4,023	11,614
Extinguishment of debt	205	2,539	0
Loss share termination	0	2,053	0
Other	20,289	26,097	20,225
Total noninterest expense	301,618	295,099	245,114
Income before income taxes	159,869	135,777	99,764
Income taxes	67,681	44,847	31,750
Net income	$ 92,188	$ 90,930	$ 68,014
Basic earnings per share (usd per share)	$ 1.97	$ 2.18	$ 1.89
Diluted earnings per share (usd per share)	1.96	2.17	1.88
Cash dividends per common share (usd per share)	$ 0.73	$ 0.71	$ 0.68