Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest Income
Loans	$ 617,632	$ 523,229	$ 463,331
Investment securities – taxable	66,292	49,409	35,569
Investment securities – tax-exempt	6,501	5,060	6,296
Other short-term investments	8,314	4,794	4,520
Total interest income	698,739	582,492	509,716
Interest Expense
Deposits	77,598	37,774	16,184
Borrowed funds	18,228	15,388	9,100
Senior and subordinated debt	14,431	12,708	12,428
Total interest expense	110,257	65,870	37,712
Net interest income	588,482	516,622	472,004
Provision for loan losses	44,027	47,854	31,290
Net interest income after provision for loan losses	544,455	468,768	440,714
Noninterest Income
Service charges on deposit accounts	49,424	48,715	48,368
Wealth management fees	48,337	43,512	41,321
Card-based fees	18,133	17,024	28,992
Capital market products income	13,931	7,721	8,171
Mortgage banking income	10,105	7,094	8,131
Merchant servicing fees	1,423	1,465	10,340
Other service charges, commissions, and fees	9,940	9,425	9,843
Net securities losses	0	0
Net securities losses			(1,876)
Other income	11,586	9,636	9,859
Total noninterest income	162,879	144,592	163,149
Noninterest Expense
Salaries and wages	197,640	181,164	182,507
Retirement and other employee benefits	42,879	43,104	41,886
Net occupancy and equipment expense	56,334	53,434	49,751
Professional services	39,941	32,681	33,689
Technology and related costs	19,758	19,220	18,068
Advertising and promotions	11,561	9,248	8,694
Amortization of other intangible assets	10,481	7,444	7,865
Federal Deposit Insurance Corporation Premium ("FDIC") Expense	8,353	10,584	8,987
Net OREO expense	2,436	1,162	4,683
Merchant card expense	0	0	8,377
Cardholder expense	0	0	7,323
Other expenses	28,995	28,236	23,956
Acquisition and integration related expenses	21,860	9,613	20,123
Delivering Excellence implementation costs	1,157	20,413	0
Total noninterest expense	441,395	416,303	415,909
Income before income tax expense	265,939	197,057	187,954
Income tax expense	66,201	39,187	89,567
Net income	$ 199,738	$ 157,870	$ 98,387
Per Common Share Data
Basic earnings per common share (EPS) (in dollars per share)	$ 1.83	$ 1.52	$ 0.96
Diluted earnings per common share (in dollars per share)	$ 1.82	$ 1.52	$ 0.96
Weighted-average common shares outstanding (in shares)	108,156	102,850	101,423
Weighted-average diluted common shares outstanding (in shares)	108,584	102,854	101,443