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Investment Securities - Securities Sold and Pledged as Collateral (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015 | Dec. 31, 2015
Available-for-sale: |  |  |  |  |
Sales proceeds | $ 0 | $ 0 | $ 68,673 | $ 1,559 |
Gross realized gains | 0 | 0 | 458 | 8 |
Gross realized losses | 0 | 0 | (64) | 0 |
Held-to-maturity Securities, Sales, Excluding Other than Temporary Impairments [Abstract] |  |  |  |  |
Sales proceeds | 0 | 1,015 | 0 | 1,015 |
Gross realized gains | 0 | 72 | 0 | 72 |
Gross realized losses | 0 | $ 0 | 0 | $ 0 |
State of California |  |  |  |  |
Available-for-sale: |  |  |  |  |
Available-for-sale securities pledged as collateral | 70,700 |  | 70,700 |  | $ 87,900
Public Deposits |  |  |  |  |
Available-for-sale: |  |  |  |  |
Available-for-sale securities pledged as collateral | 69,900 |  | 69,900 |  | 87,100
Trust Deposits |  |  |  |  |
Available-for-sale: |  |  |  |  |
Available-for-sale securities pledged as collateral | 827 |  | 827 |  | 840
Internal checking account |  |  |  |  |
Available-for-sale: |  |  |  |  |
Available-for-sale securities pledged as collateral | $ 2,100 |  | $ 2,100 |  | $ 1,100

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- Definition This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563 + Details
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- Definition This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563 + Details
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- Definition Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729 + Details
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