Note 13 - Fair Value Measurements - Measure Nonrecurring Fair Value Measurements (Details) - Fair Value, Nonrecurring [Member] - USD ($) $ in Thousands  | 
12 Months Ended | |
|---|---|---|
Dec. 31, 2021  | 
Dec. 31, 2020  | 
|
| Impaired loans | $ 663 | $ 925 | 
| Gain (loss) on impaired loans | 0 | 0 | 
| Fair Value, Inputs, Level 1 [Member] | ||
| Impaired loans | 0 | 0 | 
| Fair Value, Inputs, Level 2 [Member] | ||
| Impaired loans | 0 | 0 | 
| Fair Value, Inputs, Level 3 [Member] | ||
| Impaired loans | $ 663 | $ 925 | 
| X | ||||||||||
- Definition Represents gain (loss) on impairment loans. No definition available. 
  | 
| X | ||||||||||
- Definition Represents fair value disclosure of impaired loans. No definition available. 
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| X | ||||||||||
- Details 
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| X | ||||||||||
- Details 
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| X | ||||||||||
- Details 
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| X | ||||||||||
- Details 
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