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Investment Securities - Non-Marketable Securities (Details) | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Jun. 30, 2015 USD ($) $ / shares shares | Jul. 28, 2015 | Jun. 23, 2015 | May. 14, 2015 | Dec. 31, 2014 USD ($)
Schedule of Cost-method Investments [Line Items] |  |  |  |  |
Federal Home Loan Bank stock, par value | $ / shares | $ 100 |  |  |  |
Federal Home Loan Bank, dividend rate percentage |  |  | 14.98% | 7.67% |
Investments in low income housing tax credit funds | $ 2,800,000 |  |  |  | $ 1,800,000
Low income housing tax credits and other tax benefits | 132,000 |  |  |  |
Low income housing amortization expense | 102,000 |  |  |  |
Unfunded commitments for low income housing tax credit funds | $ 2,000,000 |  |  |  |
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 | 1,900,000 |  |  |  | 1,800,000
Subsequent event |  |  |  |  |
Schedule of Cost-method Investments [Line Items] |  |  |  |  |
Federal Home Loan Bank, dividend rate percentage |  | 10.01% |  |  |
Other assets |  |  |  |  |
Schedule of Cost-method Investments [Line Items] |  |  |  |  |
Federal Home Loan Bank stock | $ 8,400,000 |  |  |  | $ 8,200,000

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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=49127445&loc=SL49122993-202985 + Details
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