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Investment Securities - Non-Marketable Securities (Details) | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2016 USD ($) $ / shares shares | Apr. 28, 2016 | Dec. 31, 2015 USD ($)
Schedule of Cost-method Investments [Line Items] |  |  |
Federal Home Loan Bank stock, par value | $ / shares | $ 100 |  |
Investments in low income housing tax credit funds | $ 2,600,000 |  | $ 2,700,000
Low income housing tax credits and other tax benefits | 82,000 |  |
Low income housing amortization expense | 63,000 |  |
Unfunded commitments for low income housing tax credit funds | $ 1,700,000 |  |
Visa Inc. | Visa Inc. Class B common stock |  |  |
Schedule of Cost-method Investments [Line Items] |  |  |
Stockholders' Equity Note, Stock Split, Conversion Ratio | 1.6483 |  |
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 | 2,100,000 |  | $ 2,200,000
Subsequent event |  |  |
Schedule of Cost-method Investments [Line Items] |  |  |
Federal Home Loan Bank, dividend rate percentage |  | 8.90% |
Other assets |  |  |
Schedule of Cost-method Investments [Line Items] |  |  |
Federal Home Loan Bank stock | $ 8,400,000 |  |

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