CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Interest income
Loans		$ 158,691	$ 117,633	$ 106,564
Investment securities – taxable		417	939	1,057
Investment securities – tax-exempt		24,960	24,529	22,654
Mortgage-backed securities		41,584	41,361	37,450
FHLB stock and equity investments		1,595	1,306	798
Other interest earning assets		1,918	1,706	390
Total interest income		229,165	187,474	168,913
Interest expense
Deposits		35,864	20,736	14,255
FHLB borrowings		12,813	15,106	11,751
Subordinated notes		5,659	5,633	1,628
Trust preferred subordinated debentures		2,610	2,013	1,706
Other borrowings		155	16	8
Total interest expense		57,101	43,504	29,348
Net interest income		172,064	143,970	139,565
Provision for loan losses	[1]	8,437	4,675	9,780
Net interest income after provision for loan losses		163,627	139,295	129,785
Noninterest income
Deposit services		25,082	21,785	20,702
Net (loss) gain on sale of securities available for sale		(1,839)	625	2,836
Gain on sale of loans		692	1,821	2,795
Trust income		6,832	3,818	3,491
Bank owned life insurance income		2,923	2,537	2,626
Brokerage services		1,987	2,422	2,127
Other		5,096	4,465	4,834
Total noninterest income		40,773	37,473	39,411
Noninterest expense
Salaries and employee benefits		70,643	60,779	61,628
Occupancy expense		13,814	12,068	13,722
Acquisition expense		2,413	4,352	0
Advertising, travel & entertainment		2,894	2,219	2,643
ATM and debit card expense		1,090	3,889	3,136
Professional fees		4,035	3,844	4,946
Software and data processing expense		3,996	3,027	2,911
Telephone and communications		1,847	1,905	1,931
FDIC insurance		1,871	1,769	2,141
Amortization expense on intangibles		5,213	1,955	1,940
Other		12,283	10,528	14,524
Total noninterest expense		120,099	106,335	109,522
Income before income tax expense		84,301	70,433	59,674
Income tax expense		10,163	16,121	10,325
Net income		$ 74,138	$ 54,312	$ 49,349
Earnings per common share - basic (in dollars per share)		$ 2.12	$ 1.82	$ 1.82
Earnings per common share - diluted (in dollars per share)		2.11	1.81	1.81
Dividends paid on common stock (in dollars per share)		$ 1.20	$ 1.11	$ 1.01

[1] Of the $8.4 million in provision for loan losses for the year ended December 31, 2018, $302,000 related to provision expense on PCI loans. Of the $4.7 million and $9.8 million recorded in provision for loan losses for the year ended December 31, 2017 and 2016, respectively, none related to provision expense on PCI loans