Loans Receivable and Allowance for Credit Losses - Schedule of Activity in the Allowance for Credit Losses (Details) - 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
Allowance for loan losses
ALLL, beginning of period	$ 835,874	$ 734,856	$ 809,773	$ 702,052	$ 702,052
Provision for (reversal of) credit losses on loans	32,924	40,156	70,798	88,218
Gross charge-offs	(28,869)	(16,464)	(49,648)	(33,447)
Gross recoveries	1,786	1,813	10,446	3,515
Total net (charge-offs) recoveries	(27,083)	(14,651)	(39,202)	(29,932)
Foreign currency translation adjustments	341	55	687	78
ALLL, end of period	842,056	760,416	842,056	760,416	809,773
Commercial Lending | C&I
Allowance for loan losses
ALLL, beginning of period	483,384	421,288	475,613	384,319	384,319
Provision for (reversal of) credit losses on loans	18,928	27,595	36,820	63,965
Gross charge-offs	(21,960)	(8,151)	(40,345)	(9,139)
Gross recoveries	394	1,504	8,312	3,068
Total net (charge-offs) recoveries	(21,566)	(6,647)	(32,033)	(6,071)
Foreign currency translation adjustments	341	55	687	78
ALLL, end of period	481,087	442,291	481,087	442,291	475,613
Commercial Lending | CRE
Allowance for loan losses
ALLL, beginning of period	231,802	212,899	221,494	218,677	218,677
Provision for (reversal of) credit losses on loans	5,145	8,007	16,305	16,112
Gross charge-offs	(6,848)	(8,306)	(8,153)	(22,243)
Gross recoveries	1,252	18	1,705	72
Total net (charge-offs) recoveries	(5,596)	(8,288)	(6,448)	(22,171)
Foreign currency translation adjustments	0	0	0	0
ALLL, end of period	231,351	212,618	231,351	212,618	221,494
Commercial Lending | Multifamily Residential
Allowance for loan losses
ALLL, beginning of period	39,446	32,324	36,555	32,117	32,117
Provision for (reversal of) credit losses on loans	882	(3,274)	3,762	(3,073)
Gross charge-offs	0	(3)	0	(7)
Gross recoveries	12	26	23	36
Total net (charge-offs) recoveries	12	23	23	29
Foreign currency translation adjustments	0	0	0	0
ALLL, end of period	40,340	29,073	40,340	29,073	36,555
Commercial Lending | Construction and land
Allowance for loan losses
ALLL, beginning of period	17,170	15,199	15,468	17,497	17,497
Provision for (reversal of) credit losses on loans	2,799	2,654	5,392	2,349
Gross charge-offs	(1)	0	(894)	(1,996)
Gross recoveries	0	3	2	6
Total net (charge-offs) recoveries	(1)	3	(892)	(1,990)
Foreign currency translation adjustments	0	0	0	0
ALLL, end of period	19,968	17,856	19,968	17,856	15,468
Consumer Lending | SFR — Traditional
Allowance for loan losses
ALLL, beginning of period	19,230	19,281	19,040	19,413	19,413
Provision for (reversal of) credit losses on loans	(496)	(574)	(207)	(747)
Gross charge-offs	(31)	0	(152)	(9)
Gross recoveries	123	4	145	54
Total net (charge-offs) recoveries	92	4	(7)	45
Foreign currency translation adjustments	0	0	0	0
ALLL, end of period	18,826	18,711	18,826	18,711	19,040
Consumer Lending | SFR —BTHO
Allowance for loan losses
ALLL, beginning of period	37,653	27,648	34,423	25,403	25,403
Provision for (reversal of) credit losses on loans	4,769	5,638	7,999	7,883
Gross charge-offs	0	0	0	0
Gross recoveries	0	0	0	0
Total net (charge-offs) recoveries	0	0	0	0
Foreign currency translation adjustments	0	0	0	0
ALLL, end of period	42,422	33,286	42,422	33,286	34,423
Consumer Lending | Home equity loans
Allowance for loan losses
ALLL, beginning of period	5,899	4,879	5,804	3,132	3,132
Provision for (reversal of) credit losses on loans	670	369	762	2,108
Gross charge-offs	(11)	0	(11)	0
Gross recoveries	2	8	5	16
Total net (charge-offs) recoveries	(9)	8	(6)	16
Foreign currency translation adjustments	0	0	0	0
ALLL, end of period	6,560	5,256	6,560	5,256	5,804
Consumer Lending | Other Consumer
Allowance for loan losses
ALLL, beginning of period	1,290	1,338	1,376	1,494	1,494
Provision for (reversal of) credit losses on loans	227	(259)	(35)	(379)
Gross charge-offs	(18)	(4)	(93)	(53)
Gross recoveries	3	250	254	263
Total net (charge-offs) recoveries	(15)	246	161	210
Foreign currency translation adjustments	0	0	0	0
ALLL, end of period	$ 1,502	$ 1,325	$ 1,502	$ 1,325	$ 1,376