Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
INTEREST INCOME
Loans, leases and fees	$ 172,342	$ 149,777	$ 115,295
Federal funds sold and interest-bearing deposits with banks	880	569	62
Taxable investment securities and other	14,987	11,163	10,563
Tax-exempt investment securities	1,995	1,787	1,594
TOTAL INTEREST INCOME	190,204	163,296	127,514
INTEREST EXPENSE
Deposits	16,600	10,512	5,755
Federal funds purchased and securities sold under agreements to repurchase	198	69	110
Other borrowings	8,168	7,066	5,009
TOTAL INTEREST EXPENSE	24,966	17,647	10,874
NET INTEREST INCOME	165,238	145,649	116,640
Provision for loan and lease losses	6,090	4,223	1,942
NET INTEREST INCOME AFTER PROVISION FOR LOAN AND LEASE LOSSES	159,148	141,426	114,698
NONINTEREST INCOME
Service charges on deposit accounts	10,740	10,157	10,024
Commissions and fees	4,858	4,349	4,568
Income on bank owned life insurance	2,354	2,562	2,017
Gain on debt extinguishment	0	0	1,830
Gains on sales of loans	1,836	2,123	1,681
Gain on sales and calls of investment securities, net	2,524	370	241
Other income	3,123	1,769	800
TOTAL NONINTEREST INCOME	25,435	21,330	21,161
NONINTEREST EXPENSE
Salaries and employee benefits	61,166	56,107	48,640
Net occupancy expense	10,243	9,935	8,956
Furniture and equipment	8,269	8,017	6,930
FDIC insurance expense	1,577	2,248	2,086
Stationery, supplies and postage	1,797	1,727	1,529
Marketing expense	1,675	1,672	1,586
Data processing expense	1,993	1,891	1,524
Telecommunications expense	1,607	1,631	1,448
ATM and debit card expense	2,051	1,582	1,398
Core deposit intangible amortization	654	734	415
Other real estate and repossessed asset expense	181	116	181
Long-term debt prepayment fee	2,828	0	2,407
Merger related expenses	0	4,103	1,152
Other expenses	10,493	10,154	8,959
TOTAL NONINTEREST EXPENSE	104,534	99,917	87,211
Income before provision for income taxes	80,049	62,839	48,648
Provision for income taxes	27,469	21,321	16,167
NET INCOME	$ 52,580	$ 41,518	$ 32,481
PER SHARE OF COMMON STOCK:
Basic earnings (usd per share)	$ 1.10	$ 0.96	$ 0.85
Diluted earnings (usd per share)	1.09	0.95	0.85
Cash dividends (usd per share)	$ 0.40	$ 0.37	$ 0.33