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Fair Value of Assets and Liabilities - Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Nov. 29, 2013
Financial assets: |  |  |
Investment securities held-to-maturity | $ 151,032 | $ 45,097 |
Subordinated debenture |  |  |
Financial liabilities: |  |  |
Subordinated debentures |  |  | $ 4,950
Subordinated debenture | NorCal Community Bancorp Trust I |  |  |
Financial liabilities: |  |  |
Basis spread on subordinated debenture | 3.05% |  |
Subordinated debenture | NorCal Community Bancorp Trust II |  |  |
Financial liabilities: |  |  |
Basis spread on subordinated debenture | 1.40% |  |
Fair Value Hierarcy (Level 1) | Carrying Value |  |  |
Financial assets: |  |  |
Cash and cash equivalents | $ 203,545 | 48,804 |
Fair Value Hierarcy (Level 1) | Fair Value |  |  |
Financial assets: |  |  |
Cash and cash equivalents | 203,545 | 48,804 |
Fair Value Hierarchy (Level 2) | Carrying Value |  |  |
Financial assets: |  |  |
Investment securities held-to-maturity | 151,032 | 44,438 |
Interest receivable | 7,501 | 6,319 |
Financial liabilities: |  |  |
Deposits | 2,148,670 | 1,772,700 |
Interest payable | 191 | 134 |
Fair Value Hierarchy (Level 2) | Fair Value |  |  |
Financial assets: |  |  |
Investment securities held-to-maturity | 151,032 | 45,097 |
Interest receivable | 7,501 | 6,319 |
Financial liabilities: |  |  |
Deposits | 2,148,050 | 1,773,102 |
Interest payable | 191 | 134 |
Fair Value Hierarchy (Level 3) | Carrying Value |  |  |
Financial assets: |  |  |
Loans, net | 1,663,246 | 1,471,174 |
Financial liabilities: |  |  |
Subordinated debentures | 5,739 | 5,586 |
Fair Value Hierarchy (Level 3) | Fair Value |  |  |
Financial assets: |  |  |
Loans, net | 1,650,198 | 1,473,360 |
Financial liabilities: |  |  |
Subordinated debentures | $ 5,118 | $ 5,083 |

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- Definition This element represents the disclosures for fair value estimates for financial instruments required in the footnote disclosures to the financial statements. Carrying amount reprsents accrued interest payable on all forms of debt, including deposit liabilities, that has been incurred and is unpaid for time value of money. The carrying value may approximate fair value due to the short-term nature of their settlement dates. + References No definition available. + Details
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- Definition This element represents the disclosures for fair value estimates for financial instruments required in the footnote disclosures to the financial statements. Carrying amount represents interest earned but not received from loan borrowers, investment security issuers and on other forms of short-term investment for time value of money. The carrying value may approximate fair value due to the short-term nature of their settlement dates. + References No definition available. + Details
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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References No definition available. + Details
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- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
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- Definition Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits. + References No definition available. + Details
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- Definition Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Fair value of investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details
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- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -URI http://asc.fasb.org/subtopic&trid=2196772 + Details
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