LOANS AND LEASES RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES ON LOANS AND LEASES - Schedule of Allowance for Credit Losses (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 160,962	$ 141,076	$ 155,656	$ 136,775	$ 136,775
Allowance for credit losses on FDIC PCD loans, net of charge-offs		1,000		1,000
Charge-offs	(17,327)	(17,163)	(34,399)	(37,926)	(72,296)
Recoveries	2,748	4,048	6,565	7,667
Provision (benefit) for credit losses on loans and leases	17,723	18,457	36,284	39,902
Ending balance	164,106	147,418	164,106	147,418	155,656
Commercial and industrial, including specialized lending
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	41,214	30,584	37,683	29,379	29,379
Allowance for credit losses on FDIC PCD loans, net of charge-offs		1,000		1,000
Charge-offs	(3,469)	(5,996)	(7,948)	(10,503)
Recoveries	821	2,125	2,724	3,401
Provision (benefit) for credit losses on loans and leases	1,592	8,549	7,699	12,985
Ending balance	40,158	36,262	40,158	36,262	37,683
Allowance for credit losses		1,000		1,000
Multifamily
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	19,441	18,790	19,333	18,511	18,511
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0		0
Charge-offs	(4,880)	0	(7,510)	(3,834)
Recoveries	0	0	0	0
Provision (benefit) for credit losses on loans and leases	14,763	2,074	17,501	6,187
Ending balance	29,324	20,864	29,324	20,864	19,333
Commercial real estate owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	10,556	10,780	10,431	10,755	10,755
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0		0
Charge-offs	(6)	(417)	(36)	(436)
Recoveries	338	6	373	9
Provision (benefit) for credit losses on loans and leases	(662)	2,145	(542)	2,186
Ending balance	10,226	12,514	10,226	12,514	10,431
Commercial real estate non-owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	18,470	18,058	18,928	17,405	17,405
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0		0
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision (benefit) for credit losses on loans and leases	(4,967)	2,621	(5,425)	3,274
Ending balance	13,503	20,679	13,503	20,679	18,928
Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	2,672	1,264	2,225	1,250	1,250
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0		0
Charge-offs	0	0	0	0
Recoveries	0	3	0	6
Provision (benefit) for credit losses on loans and leases	131	893	578	904
Ending balance	2,803	2,160	2,803	2,160	2,225
Residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	5,713	6,163	6,499	5,968	5,968
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0		0
Charge-offs	(21)	0	(22)	0
Recoveries	1	4	2	4
Provision (benefit) for credit losses on loans and leases	558	164	(228)	359
Ending balance	6,251	6,331	6,251	6,331	6,499
Manufactured housing
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	3,338	3,800	3,391	3,829	3,829
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0		0
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision (benefit) for credit losses on loans and leases	(94)	(79)	(147)	(108)
Ending balance	3,244	3,721	3,244	3,721	3,391
Installment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	59,558	51,637	57,166	49,678	49,678
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0		0
Charge-offs	(8,951)	(10,750)	(18,883)	(23,153)
Recoveries	1,588	1,910	3,466	4,247
Provision (benefit) for credit losses on loans and leases	6,402	2,090	16,848	14,115
Ending balance	$ 58,597	$ 44,887	$ 58,597	$ 44,887	$ 57,166

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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