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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Loans Receivable and Allowance for Credit Losses - Schedule Of Composition Of Loans Held-For-Investment (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans held-for-investment	$ 55,766,772		$ 53,726,637
ALLL	(790,520)	$ (760,416)	(702,052)	$ (696,485)	$ (683,794)	$ (668,743)
Loans held-for-investment, net	54,976,252		53,024,585
Net deferred loan fees and net unamortized premiums	24,000		46,000
Commercial lending
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans held-for-investment	39,046,567		37,672,102
Commercial lending \| C&I
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans held-for-investment	18,001,529		17,397,158
ALLL	(441,538)	(442,291)	(384,319)	(378,315)	(379,984)	(392,685)
Commercial lending \| CRE
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans held-for-investment	15,231,167		14,655,340
ALLL	(227,167)	(212,618)	(218,677)	(221,244)	(194,794)	(170,592)
Commercial lending \| Multifamily residential
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans held-for-investment	5,037,284		4,953,442
ALLL	(35,187)	(29,073)	(32,117)	(31,782)	(40,254)	(34,375)
Commercial lending \| Construction and land
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans held-for-investment	776,587		666,162
ALLL	(18,530)	(17,856)	(17,497)	(12,208)	(14,322)	(10,469)
Commercial lending \| Total CRE
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans held-for-investment	21,045,038		20,274,944
Consumer lending
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans held-for-investment	16,720,205		16,054,535
Consumer lending \| Single-family residential
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans held-for-investment	14,820,911		14,175,446
ALLL	(60,876)	(51,997)	(44,816)	(48,231)	(49,523)	(55,018)
Consumer lending \| Home equity lines of credit (“HELOCs”)
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans held-for-investment	1,852,408		1,811,628
ALLL	(6,113)	(5,256)	(3,132)	(3,210)	(3,340)	(3,947)
Consumer lending \| Total residential mortgage
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans held-for-investment	16,673,319		15,987,074
Consumer lending \| Other consumer
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans held-for-investment	46,886		67,461
ALLL	$ (1,109)	$ (1,325)	$ (1,494)	$ (1,495)	$ (1,577)	$ (1,657)