CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash Flows from Operating Activities
Net income	$ 48,417	$ 71,563
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	4,531	4,899
Amortization of premiums and discounts on securities, net	2,890	1,876
Amortization of operating lease right-of-use assets	3,274	3,068
Other amortization and accretion, net	(4,402)	(1,914)
Stock based compensation	5,471	5,773
Origination of loans designated for sale	(378,069)	(234,130)
Sale of loans designated for sale	335,882	227,711
Provision for credit losses	36,279	6,199
Deferred income taxes	(6,257)	4,442
(Gains) losses on sale of securities	(1,102)	1,538
Gains on sale of loans	(10,585)	(6,683)
Gains on sale and write-downs of other real estate owned	(278)	(279)
Losses on disposition of fixed assets	790	506
Bank owned life insurance death benefits	0	(956)
Changes in operating assets and liabilities, net of effects from acquired companies:
Net increase in other assets	(27,735)	(1,585)
Net increase (decrease) in other liabilities	9,174	(6,721)
Net cash provided by operating activities	18,280	75,307
Cash Flows from Investing Activities
Maturities and repayments of debt securities available-for-sale	211,798	67,951
Maturities and repayments of debt securities held-to-maturity	53,409	30,382
Proceeds from sale of debt securities available-for-sale	96,733	122,906
Purchases of debt securities available-for-sale	(626,731)	(164,451)
Maturities of time deposits with other banks	1,495	3,664
Net new loans and principal repayments	(204,282)	(48,600)
Purchases of loans held for investment	0	(117,853)
Proceeds from sale of other real estate owned	6,174	5,153
Additions to other real estate owned	(2,004)	0
Proceeds from sale of FHLB and Federal Reserve Bank Stock	37,697	46,283
Purchase of FHLB and Federal Reserve Bank Stock	(26,976)	(36,093)
Net cash from bank acquisitions	71,965	0
Proceeds from bank owned life insurance	0	14,218
Additions to bank premises and equipment	(1,373)	(2,254)
Net cash used in investing activities	(382,095)	(78,694)
Cash Flows from Financing Activities
Net increase in deposits	826,686	495,901
Net increase (decrease) in federal funds purchased and repurchase agreements	3,387	(143,909)
Net decrease in FHLB borrowings with original maturities of three months or less	(235,000)	(267,000)
Repayments of FHLB borrowings with original maturities of more than three months	(80,000)	(63,000)
Proceeds from FHLB borrowings with original maturities of more than three months	35,000	0
Stock based employee benefit plans	(1,221)	(2,296)
Dividends paid	0	0
Net cash provided by financing activities	548,852	19,696
Net increase in cash and cash equivalents	185,037	16,309
Cash and cash equivalents at beginning of period	124,531	115,951
Cash and cash equivalents at end of period	309,568	132,260
Supplemental disclosure of cash flow information:
Cash paid during the period for interest	19,834	35,255
Cash paid during the period for taxes	21,712	13,500
Recognition of operating lease right-of-use assets	1,887	29,430
Recognition of operating lease liabilities	1,887	33,756
Supplemental disclosure of non-cash investing activities:
Transfer of debt securities from held-to-maturity to available-for-sale	0	52,796
Transfers from loans to other real estate owned	5,552	5,665
Transfers from bank premises to other real estate owned	$ 1,289	$ 0