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Loans and Allowance for Credit Losses on Loans - Pledged Loans (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Other residential | Federal Reserve Bank
Financial Instruments Owned and Pledged as Collateral [Line Items]
Collateral pledged	$ 101.1	$ 110.0
Federal Home Loan Bank of San Francisco
Financial Instruments Owned and Pledged as Collateral [Line Items]
Collateral pledged	$ 1,372.0	$ 1,351.0

X

- Definition

Amount of assets pledged to secure a debt instrument.

+ References

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-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section S99
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1
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