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Investment Securities - Securities Sold, Pledged as Collateral and Transfers (Details) - USD ($) $ in Thousands |  | 3 Months Ended |
--- | --- | --- | ---
Feb. 24, 2017 | Mar. 31, 2017 | Mar. 31, 2016 | Dec. 31, 2016
Held-to-maturity Securities, Sales, Excluding Other than Temporary Impairments [Abstract] |  |  |  |
Sales proceeds |  | $ 0 | $ 54,985 |
Gross realized gains |  | 0 | 110 |
Gross realized losses |  | 0 | 0 |
Available-for-sale: |  |  |  |
Securities transferred from available-for-sale to held-to-maturity | $ 129,000 | 128,965 | $ 0 |
Unrealized pre-tax loss from transfer of available-for-sale securities to held-to-maturity | $ 3,000 |  |  |
State of California |  |  |  |
Available-for-sale: |  |  |  |
Available-for-sale securities pledged as collateral |  | 103,600 |  | $ 109,100
Public Deposits |  |  |  |
Available-for-sale: |  |  |  |
Available-for-sale securities pledged as collateral |  | 102,800 |  | 108,300
Trust Deposits |  |  |  |
Available-for-sale: |  |  |  |
Available-for-sale securities pledged as collateral |  | 819 |  | $ 822
Internal checking account |  |  |  |
Available-for-sale: |  |  |  |
Available-for-sale securities pledged as collateral |  | $ 2,100 |  |

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- Definition Available-for-sale Securities, Transferred to Held-to-maturity Securities + References No definition available. + Details
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- Definition Available-for-sale Securities, Transferred to Held-to-maturity Securities, Unrealized Gain (Loss) + References No definition available. + Details
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- Definition Held-To-Maturity Securities, Sold Security, Realized Gain + References No definition available. + 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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- Definition The cash inflow associated with the sale of securities that had been designated as held-to-maturity. Excludes proceeds from maturities, prepayments and calls by the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26853-111562 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585 + Details
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