Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest Income
Interest and fees on loans	$ 685,911	$ 633,199	$ 552,821
Interest and dividends on investment securities:
Taxable	58,143	52,050	62,458
Tax-exempt	15,537	14,568	14,683
Dividends	6,206	6,557	6,272
Interest on federal funds sold and other short-term investments	1,126	649	369
Total interest income	766,923	707,023	636,603
Interest Expense
Savings, NOW and money market	39,787	24,824	19,671
Time	37,775	35,432	27,882
Interest on short-term borrowings	12,022	919	972
Interest on long-term borrowings and junior subordinated debentures	59,190	95,579	113,321
Total interest expense	148,774	156,754	161,846
Net Interest Income	618,149	550,269	474,757
Provision for credit losses	11,869	8,101	1,884
Net Interest Income After Provision for Credit Losses	606,280	542,168	472,873
Non-Interest Income
Trust and investment services	10,345	10,020	9,512
Insurance commissions	19,106	17,233	16,853
Service charges on deposit accounts	20,879	21,176	22,771
Gains on securities transactions, net	777	2,487	745
Fees from loan servicing	6,441	6,641	7,013
Gains on sales of loans, net	22,030	4,245	1,731
Gains on sales of assets, net	1,358	2,776	18,087
Bank owned life insurance	6,694	6,815	6,392
Change in FDIC loss-share receivable	(1,291)	(3,326)	(20,792)
Other	16,886	15,735	15,304
Total non-interest income	103,225	83,802	77,616
Non-Interest Expense
Salary and employee benefits expense	235,853	221,765	193,489
Net occupancy and equipment expense	87,140	90,521	74,492
FDIC insurance assessment	20,100	16,867	14,051
Amortization of other intangible assets	11,327	9,169	9,919
Professional and legal fees	17,755	18,945	16,859
Loss on extinguishment of debt	315	51,129	10,132
Amortization of tax credit investments	34,744	27,312	24,196
Telecommunication expenses	10,021	8,259	6,993
Other	58,870	55,108	53,124
Total non-interest expense	476,125	499,075	403,255
Income before income taxes	233,380	126,895	147,234
Income tax expense	65,234	23,938	31,062
Net Income	168,146	102,957	116,172
Dividends on preferred stock	7,188	3,813	0
Net Income Available to Common Shareholders	$ 160,958	$ 99,144	$ 116,172
Earnings Per Common Share:
Basic (in usd per share)	$ 0.63	$ 0.42	$ 0.56
Diluted (in usd per share)	0.63	0.42	0.56
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)	254,841,571	234,405,909	205,716,293
Diluted (in shares)	255,268,336	234,437,000	205,716,293