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Loans and Allowance for Credit Losses on Loans - Pledged Loans (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Federal Home Loan Bank of San Francisco
Financial Instruments Owned and Pledged as Collateral [Line Items]
Collateral pledged	$ 1,293.0	$ 1,330.0
Other residential | Federal Reserve Bank
Financial Instruments Owned and Pledged as Collateral [Line Items]
Collateral pledged	$ 102.6	$ 106.2

X

- Definition

Amount of assets pledged to secure a debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

+ Details

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X

- 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

No definition available.

+ Details

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- Details

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- Details

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- Details

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