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Fair Value - Financial Assets Accounted for at Fair Value (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | $ 88,179 | $ 93,383
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value | 73,507 |
Certificates of deposit [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 73,507 | 75,916
Equity Funds [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 499
Residential Mortgage Backed Securities [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 10,478 | 12,472
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value | 10,478 |
Collateralized Debt Obligations [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 3,685 | 4,486
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value | 3,685 |
SBA-guaranteed loan participation certificates [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale |  | 10
Municipal Bonds [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 509 |
Nonrecurring [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 88,179 | 93,383
Nonrecurring [Member] | Certificates of deposit [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 73,507 | 75,916
Nonrecurring [Member] | Equity mutual fund [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale |  | 499
Nonrecurring [Member] | Mortgage-backed securities - residential [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 10,478 | 12,472
Nonrecurring [Member] | Collateralized mortgage obligations - residential [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 3,685 | 4,486
Nonrecurring [Member] | SBA-guaranteed loan participation certificates [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale |  | 10
Nonrecurring [Member] | Municipal Securities [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 509 |
Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 499
Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Certificates of deposit [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Mortgage-backed securities - residential [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Collateralized mortgage obligations - residential [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | SBA-guaranteed loan participation certificates [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale |  | 0
Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Municipal Securities [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 0 |
Nonrecurring [Member] | Significant Observable Inputs (Level 2) [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 88,179 | 92,884
Nonrecurring [Member] | Significant Observable Inputs (Level 2) [Member] | Equity mutual fund [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale |  | 0
Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Certificates of deposit [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Equity mutual fund [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale |  | 0
Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Mortgage-backed securities - residential [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Collateralized mortgage obligations - residential [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | SBA-guaranteed loan participation certificates [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale |  | 0
Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Municipal Securities [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 0 |
Estimate of Fair Value Measurement [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 88,179 | 93,383
Estimate of Fair Value Measurement [Member] | Significant Observable Inputs (Level 2) [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | 88,179 | 92,884
Estimate of Fair Value Measurement [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-sale | $ 0 | $ 0

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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27198-111563 + Details
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
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