Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
INTEREST AND DIVIDEND INCOME
Loans, including fees	$ 119,503	$ 95,502
Interest and dividends on securities:
Taxable	16,986	16,733
Tax-exempt	4,456	5,541
Total interest and dividends on securities	21,442	22,274
Other interest income	1,503	1,277
Total interest and dividend income	142,448	119,053
INTEREST EXPENSE
Interest bearing demand deposits	3,394	3,946
Money market deposits	2,352	1,899
Savings deposits	923	522
Certificates of deposit	4,054	3,903
Total interest expense on deposits	10,723	10,270
Federal Home Loan Bank borrowings	8,232	6,337
Other short-term borrowings	870	1,556
Subordinated debt and junior subordinated debt	2,461	2,529
Total interest expense	22,286	20,692
NET INTEREST INCOME	120,162	98,361
Provision for credit losses	29,821	2,507
Net interest income after provision for credit losses	90,341	95,854
NON-INTEREST INCOME
Electronic banking fees	4,254	5,892
Net securities brokerage revenue	1,679	1,860
Bank-owned life insurance	1,769	1,319
Mortgage banking income	1,276	1,056
Net securities gains	1,491	657
Net gain on other real estate owned and other assets	169	136
Other income	3,802	3,189
Total non-interest income	28,009	27,773
NON-INTEREST EXPENSE
Salaries and wages	38,910	30,940
Employee benefits	10,373	9,989
Net occupancy	7,084	5,566
Equipment	6,039	4,833
Marketing	1,138	1,243
FDIC insurance	2,113	1,353
Amortization of intangible assets	3,374	2,514
Restructuring and merger-related expense	5,164	3,107
Other operating expenses	17,138	14,887
Total non-interest expense	91,333	74,432
Income before provision for income taxes	27,017	49,195
Provision for income taxes	3,621	8,858
NET INCOME	$ 23,396	$ 40,337
EARNINGS PER COMMON SHARE
Basic	$ 0.35	$ 0.74
Diluted	$ 0.35	$ 0.74
AVERAGE COMMON SHARES OUTSTANDING
Basic	67,486,550	54,598,499
Diluted	67,587,446	54,706,337
DIVIDENDS DECLARED PER COMMON SHARE	$ 0.32	$ 0.31
COMPREHENSIVE INCOME	$ 63,336	$ 60,110
Total Trust Fees [Member]
NON-INTEREST INCOME
NON-INTEREST INCOME	6,952	7,115
Service Charges on Deposits [Member]
NON-INTEREST INCOME
NON-INTEREST INCOME	$ 6,617	$ 6,549