CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
OPERATING ACTIVITIES:
Net income	$ 151,121	$ 76,971
Adjustments to reconcile net income to net cash provided from operating activities:
Depreciation	13,071	13,677
Deferred income/expense and capitalized servicing rights, net of amortization	(34,389)	(8,503)
Amortization of core deposit intangibles	4,997	5,867
Gain on sale of securities, net	(618)	(815)
Net change in valuation of financial instruments carried at fair value	(1,895)	2,360
Dividend Income Reinvested, Equity Securities, Operating	0	(255)
Increase in deferred taxes	4,388	1,279
Increase in current taxes payable	499	1,426
Stock-based compensation	7,012	6,893
Net change in cash surrender value of BOLI	(3,482)	(3,721)
Gain on sale of loans, excluding capitalized servicing rights	(22,623)	(34,951)
(Gain) loss on disposal of real estate held for sale and property and equipment, net	(1,452)	496
(Recapture) provision for credit losses	(28,145)	67,273
Real Estate Owned, Valuation Allowance, Provision Increase (Decrease)	0	18
Origination of loans held for sale	(912,467)	(1,032,523)
Proceeds from sales of loans held for sale	1,115,207	1,091,984
Net change in:
Other assets	23,630	(51,796)
Other liabilities	23,645	5,040
Net cash provided from operating activities	329,723	138,162
INVESTING ACTIVITIES:
Payments to Acquire Debt Securities, Available-for-sale	2,390,756	608,192
Principal repayments and maturities of securities—available-for-sale	1,136,965	311,781
Available-for-sale Securities, Sale Proceeds	59,591	128,939
Purchases of securities—held-to-maturity	(52,440)	(215,780)
Principal repayments and maturities of securities—held-to-maturity	23,842	20,691
Purchases of equity securities	(4,750)	(1,060,000)
Proceeds from sales of equity securities	4,796	610,519
Loan repayments (originations), net	660,016	(855,936)
Purchases of loans and participating interest in loans	(4,258)	(18)
Proceeds from sales of other loans	38,386	8,454
Purchases of property and equipment	(6,355)	(9,936)
Proceeds from sale of real estate held for sale and sale of other property	8,299	2,869
Proceeds from FHLB stock repurchase program	4,358	52,164
Purchase of FHLB stock	0	(40,185)
Payments for Securities Purchased under Agreements to Resell	(300,000)	0
Other	2,343	3,913
Net cash used in investing activities	(819,963)	(1,650,717)
FINANCING ACTIVITIES:
Increase in deposits, net	1,597,381	2,166,700
Repayment of long term FHLB advances	(100,000)	0
Repayment of overnight and short term FHLB advances, net	0	(300,000)
Increase in other borrowings, net	62,572	58,508
Proceeds from Issuance of Subordinated Long-term Debt	0	98,027
Cash dividends paid	(43,568)	(79,655)
Taxes paid related to net share settlement of equity awards	3,218	1,447
Cash paid for the repurchase of common stock	56,528	31,775
Net cash provided from financing activities	1,456,639	1,910,358
NET CHANGE IN CASH AND CASH EQUIVALENTS	966,399	397,803
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	1,234,183	307,735
CASH AND CASH EQUIVALENTS, END OF PERIOD	2,200,582	705,538
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Interest paid in cash	17,927	31,817
Tax paid (refunds received)	20,081	(27,515)
NON-CASH INVESTING AND FINANCING TRANSACTIONS:
Transfer of loans to real estate owned and other repossessed assets	512	1,588
Dividends Payable	$ 1,191	$ 1,179