Loans and Leases Receivable and Allowance for Credit Losses on Loans and Leases - Schedule of Allowance for Credit Losses (Details) - USD ($) $ in Thousands		12 Months Ended
Jun. 15, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		$ 130,924	$ 137,804	$ 144,176
Allowance for credit losses on FDIC PCD loans, net of charge-offs		2,576
Charge-offs		(95,066)	(77,196)	(40,381)
Recoveries		26,031	10,828	6,583
Provision (benefit) for credit losses on loans and leases		70,846	59,488	27,426
Ending balance		135,311	130,924	137,804
Allowance for credit losses on FDIC PCD loans, excluding charge-offs	$ 8,700
Commercial and industrial, including specialty lending
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		17,582	12,702	12,239
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0
Charge-offs		(16,915)	(16,248)	(1,550)
Recoveries		8,472	1,182	1,102
Provision (benefit) for credit losses on loans and leases		11,788	19,946	911
Ending balance		23,503	17,582	12,702
Commercial and industrial, including specialty lending \| Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge-offs		(16,915)
Commercial and industrial, including specialty lending \| Loans Originated Under Small Business Administration (SBA) CARES Act Paycheck Protection Program, Subsequently Determined Ineligible for Forgiveness
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge-offs			(11,000)
Multifamily
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		14,541	4,477	12,620
Allowance for credit losses on FDIC PCD loans, net of charge-offs		2,576
Charge-offs		(3,574)	(1,990)	(1,132)
Recoveries		0	337	0
Provision (benefit) for credit losses on loans and leases		5,376	11,717	(7,011)
Ending balance		16,343	14,541	4,477
Multifamily \| Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge-offs		(3,574)
Commercial real estate owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		6,454	3,213	9,512
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0
Charge-offs		(39)	0	(749)
Recoveries		34	51	500
Provision (benefit) for credit losses on loans and leases		3,433	3,190	(6,050)
Ending balance		9,882	6,454	3,213
Commercial real estate owner occupied \| Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge-offs		(39)
Commercial real estate non-owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		11,219	6,210	19,452
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0
Charge-offs		(4,527)	(6,075)	(944)
Recoveries		315	121	84
Provision (benefit) for credit losses on loans and leases		9,852	10,963	(12,382)
Ending balance		16,859	11,219	6,210
Commercial real estate non-owner occupied \| Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge-offs		(4,527)
Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		1,913	692	5,871
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0
Charge-offs		0	0	0
Recoveries		116	236	125
Provision (benefit) for credit losses on loans and leases		(547)	985	(5,304)
Ending balance		1,482	1,913	692
Construction \| Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge-offs		0
Residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		6,094	2,383	3,977
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0
Charge-offs		(69)	(17)	(130)
Recoveries		35	64	54
Provision (benefit) for credit losses on loans and leases		526	3,664	(1,518)
Ending balance		6,586	6,094	2,383
Manufactured housing
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		4,430	4,278	5,190
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0
Charge-offs		0	0	0
Recoveries		0	0	0
Provision (benefit) for credit losses on loans and leases		(191)	152	(912)
Ending balance		4,239	4,430	4,278
Installment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		68,691	103,849	75,315
Allowance for credit losses on FDIC PCD loans, net of charge-offs		0
Charge-offs		(69,942)	(52,866)	(35,876)
Recoveries		17,059	8,837	4,718
Provision (benefit) for credit losses on loans and leases		40,609	8,871	59,692
Ending balance		$ 56,417	$ 68,691	$ 103,849
Specialty lending \| Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Charge-off of certain PCD loans	$ 6,200

Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase, Excluding Charge-Offs

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Financing Receivable, Excluding Accrued Interest, Purchased With Credit Deterioration, Allowance For Credit Loss, Writeoff

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- Definition

Amount excluding accrued interest, of 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 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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- Definition

Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration.

+ References

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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.

+ References

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

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- Definition

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 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: 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

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+ 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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