Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash Flows From Operating Activities
Net income	$ 250,178	$ 202,820	$ 154,244
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	1,950	4,800	77,700
Stock-based compensation expense	16,158	14,926	10,737
Depreciation, amortization and accretion	49,018	23,168	14,893
Investment securities gain, net	9	(314)	(16,710)
Net realized gain on sale of premises and equipment, loans held for investment and OPPO	(4,777)	(500)	(1,334)
Net realized loss (gain) on sale and valuation adjustments of OREO	(181)	(40)	34
Gain on bank owned life insurance death benefit	(965)	(344)	0
Originations of loans held for sale	(116,463)	(336,455)	(491,385)
Proceeds from sale of loans held-for-sale	125,161	352,823	483,130
Change in Fair Value of Loans Held-for-sale	169	339	(508)
Deferred income tax expense (benefit)	(6,113)	(6,629)	(13,768)
Net change in:
Interest receivable	(8,889)	4,049	(7,992)
Interest payable	1,485	62	(933)
Other assets	(35,491)	6,815	(48,539)
Other liabilities	29,073	(30,535)	32,791
Net cash provided by operating activities	300,684	235,065	192,292
Cash Flows From Investing Activities
Loans originated, net of principal collected	(1,061,878)	174,463	(619,543)
Investment in low income housing tax credit partnerships	(2,850)	(1,408)	0
Purchases of Debt Securities, Available-for-sale	(186,547)	(3,128,233)	(2,118,667)
Purchases of Held-to-maturity Securities	(97,658)	(257,503)	0
Purchases of loans held for investment	0	279,734	50,035
Purchases of premises and equipment	(7,210)	(6,125)	(8,720)
Purchases of Federal Home Loan Bank stock	(68,841)	(1)	(53,240)
Proceeds from Sale of Debt Securities, Available-for-sale	741	89,219	194,697
Proceeds from Sale of Equity Securities	0	0	3,000
Proceeds from principal repayments and maturities of securities available for sale	769,991	764,253	603,129
Proceeds from Maturities, Prepayments and Calls of Held-to-maturity Securities	188,445	107,578	0
Proceeds from sales of premises and equipment and loans held for investment	37,001	15,880	2,948
Proceeds from redemption of Federal Home Loan Bank Stock	30,961	7,464	91,080
Proceeds from sales of other real estate owned and other personal property owned	200	132	1,074
Proceeds from bank owned life insurance death benefit	1,955	671	1,050
Proceeds from Termination of Cash Flow Hedging Instrument	0	0	34,442
Net cash received in business combinations	0	154,984	0
Net cash used in investing activities	(395,690)	(2,358,360)	(1,918,785)
Cash Flows From Financing Activities
Net increase (decrease) in deposits	(1,297,929)	2,402,669	3,185,167
Net increase in sweep repurchase agreements	9,155	12,154	9,422
Proceeds from employee stock purchase plan	2,110	2,350	2,028
Proceeds from Federal Home Loan Bank advances	2,928,030	30	1,331,000
Proceeds from Federal Reserve Bank borrowings	210,030	40	222,010
Proceeds from other borrowings	100	0	9,222
Payments for Federal Home Loan Bank advances	(1,981,030)	(30)	(2,277,000)
Payments for Federal Reserve Bank borrowings	(210,030)	(40)	(222,010)
Payments for other borrowings	(100)	0	(9,222)
Payments for common stock dividends	(94,314)	(83,790)	(95,509)
Repayments of Subordinated Debt	0	(35,000)	0
Payments for purchase of treasury stock	0	0	(20,000)
Payments for purchase and retirement of common stock	3,989	4,140	2,522
Net cash provided by (used in) financing activities	(437,967)	2,294,243	2,132,586
Increase (decrease) in cash and cash equivalents	(532,973)	170,948	406,093
Cash and cash equivalents at beginning of period	824,714	653,766	247,673
Supplemental Information:
Interest paid	22,160	8,484	18,631
Income taxes paid, net of refunds	72,989	60,562	43,287
Non-cash investing and financing activities:
Transfer of debt securities AFS to HTM	0	2,012,123	0
Transfer of Loans Held for Investment to Loans Held-for-sale	75,936	0	0
Loans transferred to OREO	0	0	1,033
Common stock issued in connection with acquistion	0	256,061	0
Premises and equipment expenditures incurred but not yet paid	71	63	302
Change in dividends payable on unvested shares included in other liabilities	80	51	706
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	$ 291,741	$ 824,714	$ 653,766