Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Interest income:
Loans, including fees	$ 238,282	$ 205,847
Loans held for sale	253	221
Securities-taxable	31,139	29,301
Securities-tax exempt	5,446	5,537
Short-term investments	1,163	489
Total interest income	276,283	241,395
Interest expense:
Deposits	46,138	26,959
Short-term borrowings	8,082	5,351
Long-term debt	2,809	3,421
Total interest expense	57,029	35,731
Net interest income	219,254	205,664
Provision for loan losses	18,043	12,253
Net interest income after provision for loan losses	201,211	193,411
Noninterest income:
Service charges on deposit accounts	20,367	21,448
Trust fees	15,124	11,335
Bank card and ATM fees	15,290	14,458
Investment and annuity fees and insurance commissions	6,528	6,125
Secondary mortgage market operations	3,726	3,401
Other income	9,468	9,485
Total noninterest income	70,503	66,252
Noninterest expense:
Compensation expense	83,968	80,100
Employee benefits	19,730	19,874
Personnel expense	103,698	99,974
Net occupancy expense	11,984	11,010
Equipment expense	4,679	3,546
Data processing expense	19,331	16,449
Professional services expense	8,168	9,255
Amortization of intangible assets	5,138	5,618
Deposit insurance and regulatory fees	5,406	7,948
Other real estate (income) expense	(991)	210
Other expense	18,287	16,781
Total noninterest expense	175,700	170,791
Income before income taxes	96,014	88,872
Income taxes	16,850	16,397
Net income	$ 79,164	$ 72,475
Earnings per common share-basic	$ 0.91	$ 0.83
Earnings per common share-diluted	0.91	0.83
Dividends paid per share	$ 0.27	$ 0.24
Weighted average shares outstanding-basic	85,688	85,241
Weighted average shares outstanding-diluted	85,800	85,423