CONSOLIDATED STATEMENTS OF INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
INTEREST INCOME:
Interest and fees on loans	$ 107,005	$ 106,027	$ 213,419	$ 206,483
Interest on securities:
Taxable	23,362	16,123	45,093	31,999
Nontaxable	3,344	2,554	5,527	5,647
Interest on federal funds sold	0	0	0	4
Interest on interest bearing deposits in other financial institutions	54	2,299	775	3,591
TOTAL INTEREST INCOME	133,765	127,003	264,814	247,724
INTEREST EXPENSE:
Interest on deposits	6,134	16,138	20,716	29,351
Interest on short-term borrowings	61	338	357	1,227
Interest on other borrowings (includes $(417) and $100 of interest expense/(benefit) related to derivatives reclassified from accumulated other comprehensive income/(loss) for the three months ended June 30, 2020 and 2019, respectively, and $(600) and $265 of interest expense related to derivatives reclassified from accumulated other comprehensive income for the six months ended June 30, 2020 and 2019, respectively)	3,424	3,819	7,084	7,483
TOTAL INTEREST EXPENSE	9,619	20,295	28,157	38,061
NET INTEREST INCOME	124,146	106,708	236,657	209,663
Provision for credit losses	26,796	4,918	48,316	6,553
NET INTEREST INCOME AFTER PROVISION FOR CREDIT LOSSES	97,350	101,790	188,341	203,110
NONINTEREST INCOME:
Revenue from contract with customers	16,544	20,482	34,320	38,484
Loan servicing income	379	1,338	1,342	3,067
Securities gains, net includes $2,006 and $3,580 of net security gains reclassified from accumulated other comprehensive income/(loss) for the three months ended June 30, 2020 and 2019, respectively and $3,664 and $5,155 of net security gains reclassified from accumulated other comprehensive income for the six months ended June 30, 2020 and 2019, respectively)	2,006	3,580	3,664	5,155
Unrealized gain on equity securities, net	680	112	449	370
Net gains on sale of loans held for sale	7,857	4,343	12,517	7,519
Valuation allowance on servicing rights	9	(364)	(1,556)	(953)
Income on bank owned life insurance	1,167	888	1,665	1,787
Other noninterest income	1,995	1,682	4,053	3,349
TOTAL NONINTEREST INCOME	30,637	32,061	56,454	58,778
NONINTEREST EXPENSES:
Salaries and employee benefits	50,118	49,895	100,075	100,180
Occupancy	6,502	6,426	12,973	13,033
Furniture and equipment	2,993	3,136	6,101	5,828
Professional fees	13,676	14,344	26,149	25,366
Advertising	995	2,609	3,200	4,929
Core deposit intangibles and customer relationship intangibles amortization	2,696	3,313	5,677	6,155
Other real estate and loan collection expenses	203	162	537	863
(Gain)/loss on sales/valuations of assets, net	701	(18,286)	717	(21,290)
Acquisition, integration and restructuring costs	673	929	2,049	4,543
Partnership investment in tax credit projects	791	1,465	975	1,940
Other noninterest expenses	11,091	11,105	22,845	21,781
TOTAL NONINTEREST EXPENSES	90,439	75,098	181,298	163,328
INCOME BEFORE INCOME TAXES	37,548	58,753	63,497	98,560
Income taxes (includes $614 and $880 of income tax expense reclassified from accumulated other comprehensive income/(loss) for the three months ended June 30, 2020 and 2019, respectively and $1,080 and $1,238 of income tax expense reclassified from accumulated other comprehensive income for the six months ended June 30, 2020 and 2019, respectively)	7,417	13,584	13,326	21,894
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS	$ 30,131	$ 45,169	$ 50,171	$ 76,666
EARNINGS PER COMMON SHARE - BASIC (in dollars per share)	$ 0.82	$ 1.26	$ 1.36	$ 2.18
EARNINGS PER COMMON SHARE - DILUTED (in dollars per share)	0.82	1.26	1.36	2.17
CASH DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 0.20	$ 0.16	$ 0.40	$ 0.32
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Net Unrealized Investment Gain (Loss)
NONINTEREST INCOME:
Securities gains, net includes $2,006 and $3,580 of net security gains reclassified from accumulated other comprehensive income/(loss) for the three months ended June 30, 2020 and 2019, respectively and $3,664 and $5,155 of net security gains reclassified from accumulated other comprehensive income for the six months ended June 30, 2020 and 2019, respectively)	$ 2,006	$ 3,580	$ 3,664	$ 5,155
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Other Comprehensive Income (Loss)
NONINTEREST EXPENSES:
Income taxes (includes $614 and $880 of income tax expense reclassified from accumulated other comprehensive income/(loss) for the three months ended June 30, 2020 and 2019, respectively and $1,080 and $1,238 of income tax expense reclassified from accumulated other comprehensive income for the six months ended June 30, 2020 and 2019, respectively)	614	880	1,080	1,238
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Net Gain (Loss) from Derivatives
INTEREST EXPENSE:
Interest on other borrowings (includes $(417) and $100 of interest expense/(benefit) related to derivatives reclassified from accumulated other comprehensive income/(loss) for the three months ended June 30, 2020 and 2019, respectively, and $(600) and $265 of interest expense related to derivatives reclassified from accumulated other comprehensive income for the six months ended June 30, 2020 and 2019, respectively)	(417)	100	(600)	265
Service charges and fees
NONINTEREST INCOME:
Revenue from contract with customers	10,972	14,629	22,993	27,423
Trust fees
NONINTEREST INCOME:
Revenue from contract with customers	4,977	4,825	9,999	9,299
Brokerage and insurance commissions
NONINTEREST INCOME:
Revenue from contract with customers	$ 595	$ 1,028	$ 1,328	$ 1,762