CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest Income
Interest and fees on loans	$ 1,198,908	$ 1,033,993	$ 734,474
Interest and dividends on investment securities:
Taxable	86,926	87,306	72,676
Tax-exempt	17,420	21,504	15,399
Dividends	12,023	13,209	9,812
Interest on other short-term investments	5,723	3,236	1,793
Total interest income	1,321,000	1,159,248	834,154
Interest on deposits:
Savings, NOW and money market	145,177	108,394	55,300
Time	166,693	81,959	42,546
Interest on short-term borrowings	47,862	45,930	18,034
Interest on long-term borrowings and junior subordinated debentures	63,220	65,762	58,227
Total interest expense	422,952	302,045	174,107
Net Interest Income	898,048	857,203	660,047
Provision for credit losses	24,218	32,501	9,942
Net Interest Income After Provision for Credit Losses	873,830	824,702	650,105
Non-Interest Income
Insurance commissions	10,409	15,213	18,156
Losses on securities transactions, net	(150)	(2,342)	(20)
Other-than-temporary impairment losses on securities	(2,928)	0	0
Portion recognized in other comprehensive income (before taxes)	0	0	0
Net impairment losses on securities recognized in earnings	(2,928)	0	0
Fees from loan servicing	9,794	9,319	7,384
Gains on sales of loans, net	18,914	20,515	20,814
Gains (losses) on sales of assets, net	78,333	(2,401)	(95)
Bank owned life insurance	8,232	8,691	7,338
Other	55,634	45,607	25,062
Total non-interest income	214,520	134,052	111,706
Non-Interest Expense
Salary and employee benefits expense	327,431	333,816	263,337
Net occupancy and equipment expense	118,191	108,763	92,243
FDIC insurance assessment	21,710	28,266	19,821
Amortization of other intangible assets	18,080	18,416	10,016
Professional and legal fees	20,810	34,141	25,834
Loss on extinguishment of debt	31,995	0	0
Amortization of tax credit investments	20,392	24,200	41,747
Telecommunication expenses	9,883	12,102	9,921
Other	63,063	69,357	46,154
Total non-interest expense	631,555	629,061	509,073
Income Before Income Taxes	456,795	329,693	252,738
Income tax expense	147,002	68,265	90,831
Net Income	309,793	261,428	161,907
Dividends on preferred stock	12,688	12,688	9,449
Net Income Available to Common Shareholders	$ 297,105	$ 248,740	$ 152,458
Earnings Per Common Share:
Basic (in usd per share)	$ 0.88	$ 0.75	$ 0.58
Diluted (in usd per share)	0.87	0.75	0.58
Cash dividends declared per common share (in usd per share)	$ 0.44	$ 0.44	$ 0.44
Weighted Average Number of Common Shares Outstanding:
Basic (in shares)	337,792,270	331,258,964	264,038,123
Diluted (in shares)	340,117,808	332,693,718	264,889,007
Trust and Investment Services
Non-Interest Income
Services	$ 12,646	$ 12,633	$ 11,538
Deposit Account
Non-Interest Income
Services	$ 23,636	$ 26,817	$ 21,529