CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Statement of Cash Flows [Abstract]
Net Cash Provided by (Used in) Operating Activities	$ 128,043	$ (31,568)
INVESTING ACTIVITIES
Purchases of securities	(153,587)	(80,292)
Proceeds from maturities, prepayments and calls of securities	72,951	81,156
Proceeds from sales of securities	1,917	1,349
Net proceeds from sales of Federal Home Loan Bank stock	2,924	7,826
Net decrease (increase) in loans	201,545	(491,457)
Proceeds from sale of portfolio loans	3,438	0
Purchases of premises and equipment	(1,926)	(2,862)
Proceeds from the sale of premises and equipment	74	0
Net Cash Provided by (Used in) Investing Activities	127,336	(484,280)
FINANCING ACTIVITIES
Net increase in core deposits	712,568	902,933
Net decrease in certificates of deposit	(117,782)	(71,007)
Net increase in securities sold under repurchase agreements	3,424	72,271
Net decrease in short-term borrowings	(75,000)	(196,778)
Repayments on long-term borrowings	(712)	(2,864)
Treasury shares issued-net	(302)	(594)
Cash dividends paid to common shareholders	(21,963)	(22,012)
Repurchase of common stock	0	(12,559)
Net Cash Provided by Financing Activities	500,233	669,390
Net increase in cash and cash equivalents	755,612	153,542
Cash and cash equivalents at beginning of period	229,666	197,823
Cash and Cash Equivalents at End of Period	985,278	351,365
Supplemental Disclosures
Loans transferred to held for sale	2,798	0
Interest paid	9,114	29,721
Income taxes paid, net of refunds	12,097	210
Transfers of loans to other real estate owned	$ 90	$ 513