Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities:
Net income	$ 79,519	$ 34,612
Adjustments to reconcile income to net cash provided by operating activities:
Provision for credit losses	11,672	12,450
Depreciation	5,047	5,305
Deferred tax expense	65	671
Amortization of net premium on securities	791	1,737
Accretion of net discount on acquired loans	(2,451)	(1,832)
Net change in deferred loan origination fees and costs	(282)	398
Amortization of core deposits and other intangible assets	3,993	2,197
Amortization of software implementation costs	610	639
Amortization of premium on acquired deposits	(770)	(743)
Accretion of discount on subordinated debt	190	191
Amortization of issuance costs on subordinated debt	110	108
Accretion of discount on convertible notes payable	101	1,093
Accretion of discount (amortization of premium) on Federal Home Loan Bank advances	0	64
Increase in cash surrender value of bank-owned life insurance	(1,418)	(1,222)
Impairment of premises and equipment	0	720
Impairment of other real estate owned and foreclosed assets	285	21
Federal Home Loan Bank stock dividends	(1,372)	(238)
Share-based compensation expense	1,743	1,093
Decrease (increase) in fair value of mortgage servicing rights	695	(14,777)
Net loss on disposal of premises and equipment	34	86
Net (loss) gain on other real estate owned and foreclosed assets activity	643	(164)
Net gain on sales of loans held-for-sale	(2,997)	(10,498)
Origination of loans held-for-sale	(669,412)	(899,200)
Proceeds from sales of loans held-for-sale	670,634	937,343
Changes in operating assets and liabilities:
Lease right-of-use assets	(478)	0
Accrued interest receivable	(8,675)	(6,255)
Prepaid expenses and other assets	(20,428)	(32,474)
Accrued interest payable	4,064	297
Accrued expenses and other liabilities	10,329	10,666
Deferred tax assets	1,944	0
Net cash provided by (used in) operating activities	84,186	42,288
Cash flows from investing activities:
Cash acquired in excess of cash paid in connection with Pioneer Merger	0	444,541
Proceeds from maturities of held-to-maturity securities	1,555	3,027
Purchases of available-for-sale securities	(5,201)	(66,606)
Proceeds from sale or maturities of available-for-sale securities	32,203	157,399
Loan originations, net of repayments	(272,090)	(707,439)
Purchases of premises and equipment	(1,367)	(1,795)
Proceeds from the sale of premises and equipment	0	2
Proceeds from sales of other real estate owned and foreclosed assets	1,101	867
Purchases of restricted equity securities	(33,061)	(18,549)
Proceeds from the sale or redemption of restricted equity securities	49,251	9,471
Purchase of other investments	(1,777)	(388)
Proceeds from the sale or redemption of other investments	158	745
Net cash used in investing activities	(229,228)	(178,725)
Cash flows from financing activities:
Net change in deposits	575,554	(285,868)
Net change in securities sold under agreements to repurchase	(10,854)	(40,837)
Proceeds from Federal Home Loan Bank advances	1,547,000	170,884
Repayments of Federal Home Loan Bank advances	(1,860,885)	(60,000)
Repayments of convertible notes payable	(5,456)	(15,217)
Proceeds from subordinated debt, net	0	24,466
Proceeds from issuance of common stock, net of issuance costs	44	(414)
Net cash provided by (used in) financing activities	245,403	(206,986)
Net increase (decrease) in cash and cash equivalents	100,361	(343,423)
Cash and cash equivalents, beginning of period	343,526	668,462
Cash and cash equivalents, end of period	443,887	325,039
Supplemental disclosures of cash flow information:
Interest paid on deposits	59,999	6,726
Interest paid on borrowed funds	18,675	6,605
Cash paid for income taxes, net	23,152	10,276
Non-cash investing and financing activities:
Assets acquired from Merger with Pioneer Bancshares, Inc.	0	1,085,506
Liabilities assumed from Merger with Pioneer Bancshares, Inc.	0	1,354,387
Net change in unrealized loss on available-for-sale securities and unrealized gain on fair value hedges of securities available-for-sale	(13,117)	(59,262)
Loan charge-offs	4,019	2,412
Premises and equipment transferred to other real estate owned and foreclosed assets	0	338
Loans transferred to other real estate owned and foreclosed assets	4,065	291
Premises and equipment transferred (from) to other assets	387	64
Mortgage servicing rights resulting from sale or securitization of mortgage loans	$ 7,634	$ 11,681