Loans Receivable and Allowance for Credit Losses - Schedule of Activity in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Allowance for loan losses
ALLL, beginning of period	$ 702,052	$ 668,743	$ 595,645
ALLL recognized on PCD loans	18,175
Provision for (reversal of) credit losses on loans	148,932	172,176	113,571
Gross charge-offs	(71,452)	(146,257)	(54,372)
Gross recoveries	11,613	7,639	8,118
Total net (charge-offs) recoveries	(59,839)	(138,618)	(46,254)
Foreign currency translation adjustments	453	(249)	(247)
ALLL, end of period	809,773	702,052	668,743
Accounting Standards Update 2022-02 \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses
ALLL, beginning of period			6,028
Commercial Lending \| C&I
Allowance for loan losses
ALLL, beginning of period	384,319	392,685	371,700
ALLL recognized on PCD loans	18,175
Provision for (reversal of) credit losses on loans	106,941	110,791	45,319
Gross charge-offs	(44,996)	(125,413)	(36,573)
Gross recoveries	10,721	6,505	6,803
Total net (charge-offs) recoveries	(34,275)	(118,908)	(29,770)
Foreign currency translation adjustments	453	(249)	(247)
ALLL, end of period	475,613	384,319	392,685
Commercial Lending \| C&I \| Accounting Standards Update 2022-02 \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses
ALLL, beginning of period			5,683
Commercial Lending \| CRE
Allowance for loan losses
ALLL, beginning of period	218,677	170,592	149,864
ALLL recognized on PCD loans	0
Provision for (reversal of) credit losses on loans	26,825	61,908	27,007
Gross charge-offs	(24,237)	(14,236)	(7,048)
Gross recoveries	229	413	432
Total net (charge-offs) recoveries	(24,008)	(13,823)	(6,616)
Foreign currency translation adjustments	0	0	0
ALLL, end of period	221,494	218,677	170,592
Commercial Lending \| CRE \| Accounting Standards Update 2022-02 \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses
ALLL, beginning of period			337
Commercial Lending \| Multifamily Residential
Allowance for loan losses
ALLL, beginning of period	32,117	34,375	23,373
ALLL recognized on PCD loans	0
Provision for (reversal of) credit losses on loans	4,386	(2,684)	10,454
Gross charge-offs	(8)	(10)	(3)
Gross recoveries	60	436	545
Total net (charge-offs) recoveries	52	426	542
Foreign currency translation adjustments	0	0	0
ALLL, end of period	36,555	32,117	34,375
Commercial Lending \| Multifamily Residential \| Accounting Standards Update 2022-02 \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses
ALLL, beginning of period			6
Commercial Lending \| Construction and land
Allowance for loan losses
ALLL, beginning of period	17,497	10,469	9,109
ALLL recognized on PCD loans	0
Provision for (reversal of) credit losses on loans	(45)	9,114	11,537
Gross charge-offs	(1,996)	(2,289)	(10,413)
Gross recoveries	12	203	236
Total net (charge-offs) recoveries	(1,984)	(2,086)	(10,177)
Foreign currency translation adjustments	0	0	0
ALLL, end of period	15,468	17,497	10,469
Commercial Lending \| Construction and land \| Accounting Standards Update 2022-02 \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses
ALLL, beginning of period			0
Consumer Lending \| Single-Family Residential
Allowance for loan losses
ALLL, beginning of period	44,816	55,018	35,564
ALLL recognized on PCD loans	0
Provision for (reversal of) credit losses on loans	8,398	(10,176)	19,384
Gross charge-offs	(57)	(35)	0
Gross recoveries	306	9	69
Total net (charge-offs) recoveries	249	(26)	69
Foreign currency translation adjustments	0	0	0
ALLL, end of period	53,463	44,816	55,018
Consumer Lending \| Single-Family Residential \| Accounting Standards Update 2022-02 \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses
ALLL, beginning of period			1
Consumer Lending \| HELOCs
Allowance for loan losses
ALLL, beginning of period	3,132	3,947	4,475
ALLL recognized on PCD loans	0
Provision for (reversal of) credit losses on loans	2,656	(873)	(424)
Gross charge-offs	(6)	(15)	(138)
Gross recoveries	22	73	33
Total net (charge-offs) recoveries	16	58	(105)
Foreign currency translation adjustments	0	0	0
ALLL, end of period	5,804	3,132	3,947
Consumer Lending \| HELOCs \| Accounting Standards Update 2022-02 \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses
ALLL, beginning of period			1
Consumer Lending \| Other consumer
Allowance for loan losses
ALLL, beginning of period	1,494	1,657	1,560
ALLL recognized on PCD loans	0
Provision for (reversal of) credit losses on loans	(229)	4,096	294
Gross charge-offs	(152)	(4,259)	(197)
Gross recoveries	263	0	0
Total net (charge-offs) recoveries	111	(4,259)	(197)
Foreign currency translation adjustments	0	0	0
ALLL, end of period	$ 1,376	$ 1,494	1,657
Consumer Lending \| Other consumer \| Accounting Standards Update 2022-02 \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for loan losses
ALLL, beginning of period			$ 0

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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Amount, excluding accrued interest, of foreign currency translation gain (loss) which decreases (increases) allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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