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Investment Securities - Non-Marketable Securities (Details) | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2017 USD ($) $ / shares shares | Dec. 31, 2016 USD ($) | Jul. 28, 2016
Schedule of Cost-method Investments [Line Items] |  |  |
Federal Home Loan Bank stock, par value (usd per share) | $ / shares | $ 100 |  |
Federal Home Loan Bank, dividend rate percentage |  |  | 7.00%
Investments in low income housing tax credit funds | $ 2,400,000 | $ 2,500,000 |
Low income housing tax credits and other tax benefits | 87,000 |  |
Low income housing amortization expense | 70,000 |  |
Unfunded commitments for low income housing tax credit funds | $ 1,100,000 |  |
Visa Inc. Class B common stock |  |  |
Schedule of Cost-method Investments [Line Items] |  |  |
Number of shares of securities carried at cost | shares | 16,939 |  |
Carrying value of securities carried at cost | $ 0 |  |
Fair value of Class B common stock | $ 2,500,000 | $ 2,200,000 |
Visa Inc. | Visa Inc. Class B common stock |  |  |
Schedule of Cost-method Investments [Line Items] |  |  |
Conversion rate on common stock | 1.6483 |  |
Other assets |  |  |
Schedule of Cost-method Investments [Line Items] |  |  |
Federal Home Loan Bank stock | $ 10,200,000 |  |

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- Definition Amount of investment in qualified affordable housing projects. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985 + Details
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