Consolidated Statements Of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Interest income
Interest and fees on loans	$ 309,161	$ 255,063	$ 606,148	$ 490,057
Mortgage loans held-for-sale	3,104	4,226	5,313	7,044
Interest bearing deposits with banks	5,206	3,243	10,506	6,039
Federal funds sold and securities purchased under resale agreements	0	1	0	1
Investment securities	27,721	19,888	55,677	39,016
Trading account securities	5	4	13	18
Federal Home Loan Bank and Federal Reserve Bank stock	1,439	1,455	2,794	2,753
Brokerage customer receivables	178	167	333	324
Total interest income	346,814	284,047	680,784	545,252
Interest expense
Interest on deposits	67,024	35,293	128,000	61,842
Interest on Federal Home Loan Bank advances	4,193	4,263	6,643	7,902
Interest on other borrowings	3,525	1,698	7,158	3,397
Interest on subordinated notes	2,806	1,787	4,581	3,560
Interest on junior subordinated debentures	3,064	2,836	6,214	5,299
Total interest expense	80,612	45,877	152,596	82,000
Net interest income	266,202	238,170	528,188	463,252
Provision for credit losses	24,580	5,043	35,204	13,389
Net interest income after provision for credit losses	241,622	233,127	492,984	449,863
Non-interest income
Wealth management	24,139	22,617	48,116	45,603
Mortgage banking	37,411	39,834	55,569	70,794
Total revenue from contracts with customers	40,065	37,411	79,447	75,591
Gains (losses) on investment securities, net	864	12	2,228	(339)
Fees from covered call options	643	669	2,427	2,266
Trading (losses) gains, net	(44)	124	(215)	227
Operating lease income, net	11,733	8,746	22,529	18,437
Other	14,135	14,080	31,036	25,916
Total non-interest income	98,158	95,233	179,815	180,912
Non-interest expense
Salaries and employee benefits	133,732	121,675	259,455	234,111
Equipment	12,759	10,527	24,529	20,599
Operating lease equipment depreciation	8,768	6,940	17,087	13,473
Occupancy, net	15,921	13,663	32,166	27,430
Data processing	6,204	8,752	13,729	17,245
Advertising and marketing	12,845	11,782	22,703	20,606
Professional fees	6,228	6,484	11,784	13,133
Amortization of other intangible assets	2,957	997	5,899	2,001
FDIC insurance	4,127	4,598	7,703	8,960
OREO expense, net	1,290	980	1,922	3,906
Other	24,776	20,371	47,004	39,654
Total non-interest expense	229,607	206,769	443,981	401,118
Income before taxes	110,173	121,591	228,818	229,657
Income tax expense	28,707	32,011	58,206	58,096
Net income	81,466	89,580	170,612	171,561
Preferred stock dividends	2,050	2,050	4,100	4,100
Net income applicable to common shares	$ 79,416	$ 87,530	$ 166,512	$ 167,461
Net income per common share-Basic (usd per share)	$ 1.40	$ 1.55	$ 2.94	$ 2.98
Net income per common share-Diluted (usd per share)	1.38	1.53	2.91	2.93
Cash dividends declared per common share (usd per share)	$ 0.25	$ 0.19	$ 0.50	$ 0.38
Weighted average common shares outstanding (in shares)	56,662	56,299	56,596	56,218
Dilutive potential common shares (in shares)	699	928	700	909
Average common shares and dilutive common shares (in shares)	57,361	57,227	57,296	57,127
Service charges on deposit accounts
Non-interest income
Total revenue from contracts with customers	$ 9,277	$ 9,151	$ 18,125	$ 18,008