CONSOLIDATED STATEMENTS OF INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Interest income:
Interest and fees on loans	$ 53,706	$ 47,040	$ 157,865	$ 138,422
Interest and dividends on taxable investments	13,344	13,454	40,956	38,802
Interest on nontaxable investments	4,272	4,790	13,367	14,394
Total interest income	71,322	65,284	212,188	191,618
Interest expense:
Interest on deposits	1,776	1,694	5,542	5,225
Interest on borrowings	337	587	835	1,081
Interest on subordinated debt held by unconsolidated subsidiary trusts	746	640	2,161	1,881
Total interest expense	2,859	2,921	8,538	8,187
Net interest income	68,463	62,363	203,650	183,431
Provision for loan losses	1,790	1,906	5,436	3,120
Net interest income after provision for loan losses	66,673	60,457	198,214	180,311
Noninterest revenues:
Deposit service fees	14,894	13,459	43,636	39,142
Other banking services	2,863	2,045	6,039	3,899
Employee benefit services	11,267	11,330	34,949	33,727
Insurance revenues	5,702	367	17,340	1,091
Wealth management services	5,226	4,185	15,041	12,292
Total noninterest revenues	39,952	31,386	117,005	90,151
Noninterest expenses:
Salaries and employee benefits	38,300	31,179	115,388	93,218
Occupancy and equipment	7,373	6,652	22,445	20,891
Data processing and communications	8,744	7,643	25,886	22,106
Amortization of intangible assets	1,359	843	4,204	2,642
Legal and professional fees	1,928	1,564	6,302	4,952
Office supplies and postage	1,713	1,636	5,336	4,733
Business development and marketing	2,004	1,889	6,167	5,711
FDIC insurance premiums	707	968	2,899	2,920
Acquisition expenses	2	562	342	1,318
Other expenses	4,096	3,143	11,282	9,584
Total noninterest expenses	66,226	56,079	200,251	168,075
Income before income taxes	40,399	35,764	114,968	102,387
Income taxes	13,239	10,742	37,548	31,228
Net income	$ 27,160	$ 25,022	$ 77,420	$ 71,159
Basic earnings per share (in dollars per share)	$ 0.61	$ 0.61	$ 1.75	$ 1.74
Diluted earnings per share (in dollars per share)	0.61	0.60	1.74	1.72
Cash dividends declared per share (in dollars per share)	$ 0.32	$ 0.31	$ 0.94	$ 0.91