Consolidated Statements of Cash Flows - USD ($) $ in Thousands		12 Months Ended
	Nov. 30, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Cash flows from operating activities:
Net earnings (loss)		$ 228,973	$ 126,888	$ (1,899,137)
Goodwill impairment		0	0	1,376,736
Depreciation and amortization		49,274	54,593	52,691
Amortization of net premiums on investment securities		19,683	23,809	37,488
Accretion Expense		(84,754)	(105,089)	0
Intangible asset amortization		28,267	33,143	11,419
Amortization of operating lease ROU assets		23,485	33,666	27,176
Provision for credit losses		70,600	42,801	52,000
Gain on sale of foreclosed assets, net		(203)	(819)	(586)
Provision for losses on foreclosed assets		773	1,885	1,992
Loss (gain) on sale of loans and leases, net		115	(645)	161,346
Loss (gain) on disposal of premises and equipment		199	647	(571)
Loss on sale of securities, net		0	60,400	442,413
Gain on BOLI death benefits		0	(1,100)	(416)
Unrealized (gain) loss on derivatives, foreign currencies, and credit-linked notes, net		(297)	(276)	5,629
LOCOM HFS Adjustment		9	(215)	8,461
Decrease (increase) in other assets		53,522	167,973	(214,614)
(Decrease) increase in accrued interest payable and other liabilities		(157,397)	(375,735)	45,044
Net cash provided by operating activities		255,601	77,374	135,768
Cash flows from investing activities:
Cash acquired in acquisitions, net of cash consideration paid		0	0	335,319
Net (increase) decrease in loans and leases		(1,658,721)	(662,358)	464,057
Proceeds from sales of loans and leases		261,875	2,455,814	8,524,063
Proceeds from maturities and paydowns of securities available-for-sale		478,677	243,572	261,042
Proceeds from sales of securities available-for-sale		0	693,338	3,028,011
Purchases of securities available-for-sale		(605,394)	(835,949)	(13,439)
Proceeds from maturities and paydowns of securities held-to-maturity		19,520	1,398	1,353
Purchases of FHLB and FRB stock		(17,396)	(23,440)	(304,014)
Redemptions of FHLB and FRB stock		4,727	2,013	272,162
Proceeds from sales of foreclosed assets		14,706	16,909	17,137
Purchases of premises and equipment, net		(20,830)	(13,047)	(15,219)
Proceeds from sales of premises and equipment		0	190	9,018
Proceeds from BOLI death benefits		2,124	5,058	3,946
Net decrease in equipment leased to others under operating leases		42,563	7,866	25,709
Net cash (used in) provided by investing activities		(1,478,149)	1,891,364	12,609,145
Cash flows from financing activities:
Net (decrease) increase in noninterest-bearing deposits		102,874	(54,341)	(5,722,546)
Net (decrease) increase in interest-bearing deposits		548,574	(3,155,519)	(4,359,678)
Net increase (decrease) in borrowings		(178,285)	(2,623,756)	(2,320,516)
Net proceeds from stock issuance		0	0	382,900
Payments for Repurchase of Common Stock		0
Proceeds from Issuance of Common Stock, Dividend Reinvestment Plan		0	308	69
Proceeds from Stock Options Exercised		77	0	0
Restricted stock surrendered			(2,708)	(5,419)
Common stock dividends paid			(68,298)	(48,881)
Net cash (used in) provided by financing activities		1,028,301	(4,844,102)	(9,607,559)
Net increase (decrease) in cash and cash equivalents		(194,247)	(2,875,364)	3,137,354
Cash and cash equivalents, beginning of year		2,502,212	5,377,576	2,240,222
Cash and cash equivalents, end of year		2,307,965	2,502,212	5,377,576
Supplemental disclosures of cash flow information:
Cash paid for interest		715,041	1,014,839	1,063,981
Cash paid (received) for income taxes		7,545	(14,450)	(68,168)
Loans transferred to foreclosed assets		22,844	19,978	20,915
Transfers from loans held for investment to loans held for sale		448,107	1,930,285	3,162,615
Loan, Transfer from Held-for-Sale to Held-in-Portfolio		0	1,179	513,914
Liabilities		31,256,165	30,042,915
Proceeds from Issuance of Debt		850,185	1,100,000	2,506,300
March 17, 2025 Stock Repurchase Program
Cash flows from financing activities:
Payments for Repurchase of Common Stock		(187,727)
Pacific Western Bank
Cash flows from financing activities:
Net proceeds from stock issuance				663,004
Supplemental disclosures of cash flow information:
Assets	$ 8,405,477
Business Combination, Consideration Transferred	(663,004)
Liabilities	$ 7,742,473
Parent [Member]
Cash flows from operating activities:
Earned stock compensation		23,352	15,448	28,697
Decrease (increase) in other assets		(3,438)	(42,141)	(466,018)
Cash flows from investing activities:
Cash acquired in acquisitions, net of cash consideration paid		0		26,310
Cash flows from financing activities:
Net proceeds from stock issuance		0	0	382,900
Payments for Repurchase of Common Stock		(187,727)
Restricted stock surrendered		(3,714)	(2,708)	(5,419)
Preferred stock dividends paid		(39,788)	(39,788)	(39,788)
Common stock dividends paid		(63,895)	(68,298)	$ (48,881)
Supplemental disclosures of cash flow information:
Liabilities		$ 224,129	$ 397,144