Loans Receivable and Allowance for Credit Losses - Financial Effects of Loan Modifications (Details)	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Commercial lending \| Commercial and industrial (“C&I”) \| Term Extension
Loans Modified as TDRs
Weighted average of loans (in years)	1 year 9 months 18 days	10 months 24 days
Commercial lending \| Commercial and industrial (“C&I”) \| Payment Delay
Loans Modified as TDRs
Weighted average of loans (in years)	1 year 8 months 12 days	1 year
Commercial lending \| CRE \| Term Extension
Loans Modified as TDRs
Weighted average of loans (in years)	1 year 6 months	2 years
Commercial lending \| CRE \| Payment Delay
Loans Modified as TDRs
Weighted average of loans (in years)	1 year 8 months 12 days	0 years
Commercial lending \| CRE \| Interest Rate Below Market Reduction
Loans Modified as TDRs
Weighted-Average Interest Rate Reduction	2.75%
Consumer lending \| HELOCs \| Term Extension
Loans Modified as TDRs
Weighted average of loans (in years)	0 years	14 years 9 months 18 days
Consumer lending \| HELOCs \| Payment Delay
Loans Modified as TDRs
Weighted average of loans (in years)	3 years 2 months 12 days	0 years
Consumer lending \| HELOCs \| Interest Rate Below Market Reduction
Loans Modified as TDRs
Weighted-Average Interest Rate Reduction	0.25%	0.00%
Consumer lending \| Real estate loan \| Term Extension \| Single-family residential
Loans Modified as TDRs
Weighted average of loans (in years)	0 years
Consumer lending \| Real estate loan \| Payment Delay \| Single-family residential
Loans Modified as TDRs
Weighted average of loans (in years)	8 months 12 days
Consumer lending \| Real estate loan \| Interest Rate Below Market Reduction \| Single-family residential
Loans Modified as TDRs
Weighted-Average Interest Rate Reduction	0.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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-Section 50
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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Percentage of decrease in weighted average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty.

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