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Note 7 - Fair Value Measurements - Change in Fair Value Measurement Impacts Net Income (Details) $ in Thousands | Jun. 30, 2020 USD ($) | Dec. 31, 2019 USD ($)
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Interest Rate Contract [Member] | Valuation, Market Approach [Member] | Pull-through Rate [Member] | Minimum [Member] |  |  |
Derivative asset (liability) | [1] | 0.8582 |
Derivative asset (liability) | [1] | (0.8582) |
Interest Rate Contract [Member] | Valuation, Market Approach [Member] | Pull-through Rate [Member] | Maximum [Member] |  |  |
Derivative asset (liability) | [1] | 1.0000 |
Derivative asset (liability) | [1] | (1.0000) |
Interest Rate Contract [Member] | Valuation, Market Approach [Member] | Pull-through Rate [Member] | Weighted Average [Member] |  |  |
Derivative asset (liability) | [1] | (0.8707) |
Derivative asset (liability) | [1] | 0.8707 |
Interest Rate Contract [Member] | Valuation, Market Approach [Member] | Current Reference Price [Member] | Minimum [Member] |  |  |
Derivative asset (liability) |  | 1.0272 | 1.0149
Derivative asset (liability) |  | (1.0272) | (1.0149)
Interest Rate Contract [Member] | Valuation, Market Approach [Member] | Current Reference Price [Member] | Maximum [Member] |  |  |
Derivative asset (liability) |  | 1.0546 | 1.0206
Derivative asset (liability) |  | (1.0546) | (1.0206)
Interest Rate Contract [Member] | Reported Value Measurement [Member] |  |  |
Interest rate loan contracts |  |  | $ 1
Forward contracts |  | $ (21) |
Interest Rate Contract [Member] | Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Interest rate loan contracts |  |  | $ 1
Forward contracts |  | (21) |
Forward Contracts [Member] | Valuation, Market Approach [Member] | Current Reference Price [Member] | Minimum [Member] |  |  |
Derivative asset (liability) |  |  | 1.0149
Derivative asset (liability) |  |  | (1.0149)
Forward Contracts [Member] | Valuation, Market Approach [Member] | Current Reference Price [Member] | Maximum [Member] |  |  |
Derivative asset (liability) |  |  | 1.0328
Derivative asset (liability) |  |  | (1.0328)
Forward Contracts [Member] | Reported Value Measurement [Member] |  |  |
Interest rate loan contracts |  | 81 |
Forward contracts |  |  | $ (4)
Forward Contracts [Member] | Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Interest rate loan contracts |  | $ 81 |
Forward contracts |  |  | $ (4)
Forward Contract [Member] | Valuation, Market Approach [Member] | Pull-through Rate [Member] | Minimum [Member] |  |  |
Derivative asset (liability) |  | 0.8582 |
Derivative asset (liability) |  | (0.8582) |
Forward Contract [Member] | Valuation, Market Approach [Member] | Pull-through Rate [Member] | Maximum [Member] |  |  |
Derivative asset (liability) |  | 1.0000 |
Derivative asset (liability) |  | (1.0000) |
Forward Contract [Member] | Valuation, Market Approach [Member] | Pull-through Rate1 [Member] | Weighted Average [Member] |  |  |
Derivative asset (liability) |  | (0.8707) |
Derivative asset (liability) |  | 0.8707 |
Forward Contract [Member] | Valuation, Market Approach [Member] | Current Reference Price [Member] | Minimum [Member] |  |  |
Derivative asset (liability) |  | 1.0223 |
Derivative asset (liability) |  | (1.0223) |
Forward Contract [Member] | Valuation, Market Approach [Member] | Current Reference Price [Member] | Maximum [Member] |  |  |
Derivative asset (liability) |  | 1.0558 |
Derivative asset (liability) |  | (1.0558) |
[1] | all contracts are valued using the same pull-through rate

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