Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net income	$ 103,533,000	$ 59,182,000	$ 43,164,000
Adjustments to reconcile income to net cash provided by operating activities:
Provision for credit losses	18,247,000	18,050,000	3,000,000
Depreciation and amortization on premises and equipment	7,420,000	7,953,000	7,181,000
Deferred tax expense	3,012,000	9,203,000	3,145,000
Amortization of net premium on securities	1,004,000	2,076,000	3,399,000
Accretion of net discount on acquired loans	(3,204,000)	(1,308,000)	(1,142,000)
Net change in deferred loan origination fees and costs	(1,178,000)	1,182,000	617,000
Amortization of core deposits and other intangible assets	4,822,000	4,215,000	1,417,000
Amortization of premium on acquired deposits	(966,000)	(1,052,000)	(45,000)
Accretion of discount on subordinated debt	286,000	254,000	256,000
Amortization of issuance costs on subordinated debt	147,000	145,000	93,000
Accretion of discount on convertible notes payable	101,000	1,131,000	746,000
Accretion of discount on Federal Home Loan Bank advances	0	76,000	0
Increase in cash surrender value of bank-owned life insurance	(1,928,000)	(1,682,000)	(1,276,000)
Impairment of premises and equipment	0	720,000	0
Impairment of other real estate owned and foreclosed assets	286,000	94,000	217,000
Federal Home Loan Bank stock dividends	(1,560,000)	(712,000)	(407,000)
Share-based compensation expense	2,127,000	1,448,000	2,998,000
Decrease (increase) in fair value of mortgage servicing rights	6,649,000	(12,418,000)	5,606,000
Net loss on sales of loans held-for-investment	0	0	701,000
Net loss on disposal of premises and equipment	120,000	86,000	76,000
Net loss (gain) on other real estate owned and foreclosed assets activity	106,000	(164,000)	(824,000)
Net gain on sales of loans held-for-sale	(3,491,000)	(11,782,000)	(61,403,000)
Origination of loans held-for-sale	(791,017,000)	(1,090,759,000)	(2,165,255,000)
Proceeds from sales of loans held-for-sale	788,367,000	1,137,793,000	2,292,828,000
Changes in operating assets and liabilities:
Lease right-of-use assets	(660,000)	3,282,000	0
Accrued interest receivable	(8,556,000)	(9,835,000)	655,000
Prepaid expenses and other assets	(11,397,000)	(22,992,000)	(6,769,000)
Accrued interest payable	7,782,000	3,022,000	(223,000)
Accrued expenses and other liabilities	5,124,000	(293,000)	(15,646,000)
Net cash provided by (used in) operating activities	125,176,000	96,915,000	113,109,000
Cash flows from investing activities:
Cash acquired in excess of cash paid in connection with Pioneer Merger	0	444,542,000	0
Purchases of held-to-maturity securities	0	(335,000)	0
Proceeds from maturities of held-to-maturity securities	2,007,000	3,626,000	13,835,000
Purchases of available-for-sale securities	(21,555,000)	(66,606,000)	(248,736,000)
Proceeds from sale or maturities of available-for-sale securities	41,669,000	170,410,000	131,899,000
Loan originations, net of repayments	(362,778,000)	(1,064,293,000)	(215,281,000)
Proceeds from the sale of loans held-for-sale previously classified as held-for-investment	0	0	18,544,000
Purchases of premises and equipment	(4,268,000)	(2,196,000)	(3,455,000)
Proceeds from the sale of premises and equipment	0	2,000	5,000
Proceeds from sales of other real estate owned and foreclosed assets	5,952,000	867,000	2,089,000
Purchases of restricted equity securities	(51,076,000)	(39,785,000)	(57,000)
Proceeds from the sale or redemption of restricted equity securities	64,779,000	15,842,000	7,400,000
Purchase of other investments	(2,677,000)	(939,000)	(686,000)
Proceeds from the sale or redemption of other investments	668,000	745,000	519,000
Net cash used in investing activities	(327,279,000)	(538,120,000)	(293,924,000)
Cash flows from financing activities:
Net change in deposits	610,007,000	(280,914,000)	701,444,000
Net change in securities sold under agreements to repurchase	(12,028,000)	(55,372,000)	(23,278,000)
Proceeds from Federal Home Loan Bank advances	2,041,468,000	760,885,000	0
Repayments of Federal Home Loan Bank advances	(2,295,885,000)	(317,000,000)	(30,411,000)
Proceeds from subordinated debt, net	0	24,466,000	0
Proceeds from issuance of common stock, net of issuance costs	(167,000)	(579,000)	(456,000)
Repayments of convertible notes payable	(5,456,000)	(15,217,000)	0
Net cash provided by financing activities	337,939,000	116,269,000	647,299,000
Net increase (decrease) in cash and cash equivalents	135,836,000	(324,936,000)	466,484,000
Cash and cash equivalents, beginning of period	343,526,000	668,462,000	201,978,000
Cash and cash equivalents, end of period	479,362,000	343,526,000	668,462,000
Supplemental disclosures of cash flow information:
Interest paid on deposits	92,085,000	12,040,000	8,753,000
Interest paid on borrowed funds	20,459,000	14,118,000	5,667,000
Cash paid for income taxes, net	28,459,000	6,183,000	6,601,000
Non-cash investing and financing activities:
Assets acquired from merger with Pioneer Bancshares, Inc.	0	1,085,506,000	0
Liabilities assumed from merger with Pioneer Bancshares, Inc.	0	1,354,387,000	0
Right-of-use lease assets obtained in exchange for lessee operating lease liabilities	2,696,000	35,212,000	0
Net change in unrealized loss on available-for-sale securities and unrealized gain on fair value hedges of securities available-for-sale	1,291,000	(45,647,000)	(9,870,000)
Loan charge-offs	9,672,000	2,587,000	4,861,000
Premises and equipment transferred to other real estate owned and foreclosed assets	0	338,000	1,038,000
Loans transferred to other real estate owned and foreclosed assets	4,086,000	1,331,000	2,577,000
Mortgage servicing rights resulting from sale or securitization of mortgage loans	$ 9,253,000	$ 14,287,000	$ 23,854,000