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
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2022
Allowance for loan losses
Allowance for loan losses, start of period	$ 670,280	$ 619,893	$ 668,743	$ 595,645
Provision for (reversal of) credit losses on loans	36,762	24,025	60,916	42,545
Gross charge-offs	(25,322)	(9,755)	(50,006)	(11,792)
Gross recoveries	2,187	2,218	4,294	3,646
Total net (charge-offs) recoveries	(23,135)	(7,537)	(45,712)	(8,146)
Foreign currency translation adjustment	(113)	(981)	(153)	(672)
Allowance for loan losses, end of period	683,794	635,400	683,794	635,400
Commercial lending \| C&I
Allowance for loan losses
Allowance for loan losses, start of period	373,631	376,325	392,685	371,700
Provision for (reversal of) credit losses on loans	17,783	5,259	18,057	4,581
Gross charge-offs	(13,134)	(7,335)	(34,132)	(9,235)
Gross recoveries	1,817	2,065	3,527	3,276
Total net (charge-offs) recoveries	(11,317)	(5,270)	(30,605)	(5,959)
Foreign currency translation adjustment	(113)	(981)	(153)	(672)
Allowance for loan losses, end of period	379,984	375,333	379,984	375,333
Commercial lending \| CRE
Allowance for loan losses
Allowance for loan losses, start of period	187,460	155,067	170,592	149,864
Provision for (reversal of) credit losses on loans	18,287	15,685	37,419	20,361
Gross charge-offs	(11,103)	(2,366)	(13,501)	(2,372)
Gross recoveries	150	119	284	315
Total net (charge-offs) recoveries	(10,953)	(2,247)	(13,217)	(2,057)
Foreign currency translation adjustment	0	0	0	0
Allowance for loan losses, end of period	194,794	168,505	194,794	168,505
Commercial lending \| Construction and land
Allowance for loan losses
Allowance for loan losses, start of period	10,819	9,322	10,469	9,109
Provision for (reversal of) credit losses on loans	4,422	1,995	5,803	2,205
Gross charge-offs	(920)	0	(2,144)	0
Gross recoveries	1	8	194	11
Total net (charge-offs) recoveries	(919)	8	(1,950)	11
Foreign currency translation adjustment	0	0	0	0
Allowance for loan losses, end of period	14,322	11,325	14,322	11,325
Commercial lending \| Multifamily residential
Allowance for loan losses
Allowance for loan losses, start of period	37,418	24,526	34,375	23,373
Provision for (reversal of) credit losses on loans	2,628	(1,604)	5,660	(469)
Gross charge-offs	0	0	(6)	0
Gross recoveries	208	16	225	28
Total net (charge-offs) recoveries	208	16	219	28
Foreign currency translation adjustment	0	0	0	0
Allowance for loan losses, end of period	40,254	22,938	40,254	22,938
Consumer lending \| HELOCs
Allowance for loan losses
Allowance for loan losses, start of period	3,563	4,971	3,947	4,475
Provision for (reversal of) credit losses on loans	(232)	(444)	(664)	136
Gross charge-offs	0	(6)	0	(97)
Gross recoveries	9	5	57	11
Total net (charge-offs) recoveries	9	(1)	57	(86)
Foreign currency translation adjustment	0	0	0	0
Allowance for loan losses, end of period	3,340	4,526	3,340	4,526
Consumer lending \| Other consumer
Allowance for loan losses
Allowance for loan losses, start of period	1,467	1,675	1,657	1,560
Provision for (reversal of) credit losses on loans	240	(367)	108	(212)
Gross charge-offs	(130)	(48)	(188)	(88)
Gross recoveries	0	0	0	0
Total net (charge-offs) recoveries	(130)	(48)	(188)	(88)
Foreign currency translation adjustment	0	0	0	0
Allowance for loan losses, end of period	1,577	1,260	1,577	1,260
Consumer lending \| Single-family residential
Allowance for loan losses
Allowance for loan losses, start of period	55,922	48,007	55,018	35,564
Provision for (reversal of) credit losses on loans	(6,366)	3,501	(5,467)	15,943
Gross charge-offs	(35)	0	(35)	0
Gross recoveries	2	5	7	5
Total net (charge-offs) recoveries	(33)	5	(28)	5
Foreign currency translation adjustment	0	0	0	0
Allowance for loan losses, end of period	$ 49,523	$ 51,513	$ 49,523	$ 51,513
Accounting Standards Update 2022-02
Allowance for loan losses
Impact of ASU 2022-02 adoption					$ 6,028
Accounting Standards Update 2022-02 \| Commercial lending \| C&I
Allowance for loan losses
Impact of ASU 2022-02 adoption					5,683
Accounting Standards Update 2022-02 \| Commercial lending \| CRE
Allowance for loan losses
Impact of ASU 2022-02 adoption					337
Accounting Standards Update 2022-02 \| Commercial lending \| Construction and land
Allowance for loan losses
Impact of ASU 2022-02 adoption					0
Accounting Standards Update 2022-02 \| Commercial lending \| Multifamily residential
Allowance for loan losses
Impact of ASU 2022-02 adoption					6
Accounting Standards Update 2022-02 \| Consumer lending \| HELOCs
Allowance for loan losses
Impact of ASU 2022-02 adoption					1
Accounting Standards Update 2022-02 \| Consumer lending \| Other consumer
Allowance for loan losses
Impact of ASU 2022-02 adoption					0
Accounting Standards Update 2022-02 \| Consumer lending \| Single-family residential
Allowance for loan losses
Impact of ASU 2022-02 adoption					$ 1

Financing Receivable Allowance For Credit Loss Excluding Accrued Interest Impact of Adoption

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- Definition

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

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

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Amount, after recovery, of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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