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Investment Securities - Non-marketable Securities (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 USD ($) $ / shares shares | Dec. 31, 2020 USD ($) shares | Feb. 16, 2022
Marketable Securities [Line Items] |  |  |
Federal Home Loan Bank stock, par value (usd per share) | $ / shares | $ 100 |  |
Investments in low income housing tax credit funds | $ 3,000,000 | $ 3,500,000 |
Low income housing tax credits and other tax benefits | 645,000 |  |
Low income housing amortization expense | 542,000 |  |
Unfunded commitments for low income housing tax credit funds | 422,000 |  |
Other assets |  |  |
Marketable Securities [Line Items] |  |  |
Federal Home Loan Bank stock | $ 16,700,000 | $ 11,900,000 |
Visa Inc. Class B Common Stock |  |  |
Marketable Securities [Line Items] |  |  |
Number of shares of securities carried at cost (in shares) | shares | 10,439 | 10,439 |
Fair value of Class B common stock | $ 0 | $ 0 |
Equity securities | $ 3,700,000 |  |
Visa Inc. | Visa Inc. Class B common stock |  |  |
Marketable Securities [Line Items] |  |  |
Stock split ratio | 1.6181 | 1.6228 |
Subsequent event |  |  |
Marketable Securities [Line Items] |  |  |
Federal Home Loan Bank, dividend rate percentage |  |  | 6.00%

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- Definition Amortization Method Qualified Affordable Housing Project Investments, Tax Credits + References No definition available. + Details
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- Definition Amount of investment in qualified affordable housing projects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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- Definition Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 325 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=123599499&loc=d3e63345-112809 + Details
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