Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
INTEREST INCOME
Loans, including fees	$ 656,077	$ 737,932	$ 683,042
Investment securities:
Taxable	58,173	62,556	56,044
Tax-exempt	21,047	14,218	12,076
Loans held for sale	2,077	1,351	1,159
Other interest income	5,504	9,249	6,193
Total Interest Income	742,878	825,306	758,514
INTEREST EXPENSE
Deposits	70,045	131,775	87,712
Short-term borrowings	5,227	14,543	8,489
Long-term borrowings	38,398	30,599	31,857
Total Interest Expense	113,671	176,917	128,058
Net Interest Income	629,207	648,389	630,456
Provision for credit losses	76,920	32,825	46,907
Net Interest Income After Provision for Credit Losses	552,287	615,564	583,549
NON-INTEREST INCOME
Non-interest income before investment securities gains	226,335	211,427	195,488
Investment securities gains, net	3,053	4,733	37
Total Non-Interest Income	229,388	216,160	195,525
NON-INTEREST EXPENSE
Salaries and employee benefits	324,395	311,934	303,202
Net occupancy	53,013	52,826	51,678
Data processing and software	48,073	44,679	41,286
Other outside services	31,432	39,989	33,758
Equipment	13,885	13,575	13,243
Professional fees	12,835	13,134	14,161
State taxes	12,613	8,894	9,590
FDIC insurance	8,865	7,780	10,993
Amortization of TCI	6,126	6,021	11,449
Prepayment penalty on FHLB advances	2,878	4,326	0
Intangible amortization	529	1,427	0
Other	64,796	63,151	56,744
Total Non-Interest Expense	579,440	567,736	546,104
Income Before Income Taxes	202,235	263,988	232,970
Income taxes	24,194	37,649	24,577
Net Income	178,040	226,339	208,393
Preferred stock dividends	(2,135)	0	0
Net Income Available to Common Shareholders	$ 175,905	$ 226,339	$ 208,393
PER SHARE:
Net Income (Basic) (in dollars per share)	$ 1.08	$ 1.36	$ 1.19
Net Income (Diluted) (in dollars per share)	1.08	1.35	1.18
Cash Dividends (in dollars per share)	$ 0.56	$ 0.56	$ 0.52
Commercial banking
NON-INTEREST INCOME
Non-interest income before investment securities gains	$ 70,286	$ 71,117	$ 63,929
Consumer banking
NON-INTEREST INCOME
Non-interest income before investment securities gains	41,598	49,503	48,422
Wealth management
NON-INTEREST INCOME
Non-interest income before investment securities gains	59,058	55,678	52,148
Mortgage banking
NON-INTEREST INCOME
Non-interest income before investment securities gains	42,309	23,099	19,026
Other
NON-INTEREST INCOME
Non-interest income before investment securities gains	$ 13,084	$ 12,030	$ 11,963