CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Operating Activities:
Net income	$ 180,198	$ 127,391
Adjustments to reconcile net income to net cash provided by operating activities
Provision for credit losses	23,045	4,106
Depreciation, amortization and accretion, net	18,798	24,526
Stock-based compensation expense	8,295	7,891
Amortization of premium on securities, net	275	893
Accretion of discount and deferred fees on loans, net	(4,263)	(7,540)
Mortgage servicing rights fair value changes, net of economic hedge	10,863	(37,349)
Non-designated derivatives fair value changes, net	(2,805)	(4,046)
Originations and purchases of mortgage loans held-for-sale	(366,006)	(887,393)
Early buy-out exercises of mortgage loans held-for-sale guaranteed by U.S. government agencies, net of subsequent paydowns or payoffs	(6,334)	(4,065)
Proceeds from sales of mortgage loans held-for-sale	366,509	1,085,471
Bank owned life insurance (“BOLI”) loss (income)	1,351	(48)
Decrease in trading securities, net	1,025	209
Decrease in brokerage customer receivables, net	345	3,180
Gains on mortgage loans sold	(10,795)	(20,690)
(Gains) losses on investment securities, net	(1,398)	2,782
Losses (gains) on sales of premises and equipment, net	93	(9)
Losses (gains) on sales and fair value adjustments of other real estate owned, net	99	(1,038)
(Increase) decrease in accrued interest receivable and other assets, net	(97,024)	110,691
(Decrease) increase in accrued interest payable and other liabilities, net	(53,830)	53,062
Net Cash Provided by Operating Activities	68,441	458,024
Investing Activities:
Proceeds from maturities and calls of available-for-sale securities	1,008,597	119,041
Proceeds from maturities and calls of held-to-maturity securities	40,342	66,966
Proceeds from sales of available-for-sale securities	0	0
Proceeds from sales of equity securities with readily determinable fair value	23,592	18,753
Proceeds from sales and capital distributions of equity securities without readily determinable fair value	67	250
Purchases of available-for-sale securities	(996,433)	(996,293)
Purchases of held-to-maturity securities	(6,443)	(560,903)
Purchases of equity securities with readily determinable fair value	(23,697)	(23,255)
Purchases of equity securities without readily determinable fair value	(4,850)	(1,010)
Redemptions (purchases) of Federal Home Loan Bank and Federal Reserve Bank stock, net	20,198	(785)
Distributions from investments in partnerships, net	2,794	124
Proceeds from sales of other real estate owned	435	2,497
Decrease in interest-bearing deposits with banks, net	424,842	1,359,947
Increase in loans, net	(365,885)	(472,409)
Redemption of BOLI	0	960
Purchases of premises and equipment, net	(9,139)	(7,722)
Net Cash Provided by (Used for) Investing Activities	114,420	(493,839)
Financing Activities:
(Decrease) increase in deposit accounts, net	(184,335)	123,733
Decrease in other borrowings, net	(13,968)	(14,928)
Increase in Federal Home Loan Bank advances, net	0	0
Cash payments to settle contingent consideration liabilities recognized in business combinations	(57)	0
Issuance of common shares resulting from the exercise of stock options and employee stock purchase plan	3,579	4,829
Common stock repurchases for tax withholdings related to stock-based compensation	(1,662)	0
Dividends paid	(31,398)	(26,452)
Net Cash (Used for) Provided by Financing Activities	(227,841)	87,182
Net (Decrease) Increase in Cash and Cash Equivalents	(44,980)	51,367
Cash and Cash Equivalents at Beginning of Period	490,966	411,205
Cash and Cash Equivalents at End of Period	$ 445,986	$ 462,572