CONSOLIDATED STATEMENTS OF INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
INTEREST INCOME:
Interest and fees on loans	$ 85,651	$ 66,898
Interest on securities:
Taxable	11,577	8,253
Nontaxable	3,579	5,191
Interest on federal funds sold	0	0
Interest on interest bearing deposits in other financial institutions	407	209
TOTAL INTEREST INCOME	101,214	80,551
INTEREST EXPENSE:
Interest on deposits	5,766	3,730
Interest on short-term borrowings	268	137
Interest on other borrowings	3,596	3,656
TOTAL INTEREST EXPENSE	9,630	7,523
NET INTEREST INCOME	91,584	73,028
Provision for loan losses	4,263	3,641
NET INTEREST INCOME AFTER PROVISION FOR LOAN LOSSES	87,321	69,387
NONINTEREST INCOME:
Service charges and fees	10,079	9,457
Loan servicing income	1,754	1,724
Trust fees	4,680	3,631
Brokerage and insurance commissions	907	1,036
Securities gains, net	1,441	2,482
Unrealized loss on equity securities, net	(28)	0
Net gains on sale of loans held for sale	4,051	6,147
Valuation allowance on commercial servicing rights	(2)	5
Income on bank owned life insurance	614	617
Other noninterest income	1,220	794
TOTAL NONINTEREST INCOME	24,716	25,893
NONINTEREST EXPENSES:
Salaries and employee benefits	48,710	41,767
Occupancy	6,043	5,073
Furniture and equipment	2,749	2,501
Professional fees	8,459	8,309
FDIC insurance assessments	989	807
Advertising	1,940	2,424
Core deposit intangibles and customer relationship intangibles amortization	1,863	1,171
Other real estate and loan collection expenses	732	828
(Gain)/loss on sales/valuations of assets, net	(197)	412
Restructuring expenses	2,564	0
Other noninterest expenses	9,794	8,448
TOTAL NONINTEREST EXPENSES	83,646	71,740
INCOME BEFORE INCOME TAXES	28,391	23,540
Income taxes	5,123	5,530
NET INCOME	23,268	18,010
Preferred dividends	(13)	(19)
Interest expense on convertible preferred debt	0	5
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS	$ 23,255	$ 17,996
EARNINGS PER COMMON SHARE - BASIC (in dollars per share)	$ 0.76	$ 0.68
EARNINGS PER COMMON SHARE - DILUTED (in dollars per share)	0.76	0.68
CASH DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 0.13	$ 0.11