Note 8 - Stock-based Compensation (Tables)
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12 Months Ended | 
Mar. 29, 2020  | 
| Notes Tables | 
 
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| Share-based Payment Arrangement, Option, Activity [Table Text Block] | 
  |   |    |     |    |     |   |    |     |    |    |     |    |     |   |    |     |    |    |     |     |     |    |     |    |    |     |     |     |     |   |    |     |    |    |     |    |    |     |    |    |     |    |     |   |    |     |    |    |     |    |    |     |    |    |     |    |     |   |    |     |    |    |     |    |    |     |    |    |     |    |     |   Outstanding at Beginning of Period   |    |  $ |  7.45  |    |    |    |  457,500  |    |    |  $ |  7.93  |    |    |    |  395,000  |    |     |   Granted   |    |    |  4.76  |    |    |    |  125,000  |    |    |    |  5.90  |    |    |    |  110,000  |    |     |   Exercised   |    |    |  6.20  |    |    |    |  (10,000  |  ) |    |    |  -  |    |    |    |  -  |    |     |   Forfeited   |    |    |  7.07  |    |    |    |  (55,000  |  ) |    |    |  7.83  |    |    |    |  (47,500  |  ) |     |   Outstanding at End of Period   |    |    |  6.86  |    |    |    |  517,500  |    |    |    |  7.45  |    |    |    |  457,500  |    |     |   Exercisable at End of Period   |    |    |  7.74  |    |    |    |  347,500  |    |    |    |  8.03  |    |    |    |  292,500  |    |      
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| Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] | 
  |   |    |     |    |     |   |    |     |    |    |     |    |     |   Number of options issued   |    |    |  125,000  |    |    |    |  110,000  |    |     |   Grant date   |    |        |  June 13, 2019  |    |    |        |  June 13, 2018  |    |     |   Dividend yield   |    |    |  6.72  |  % |    |    |  5.42  |  % |     |   Expected volatility   |    |    |  25.00  |  % |    |    |  25.00  |  % |     |   Risk free interest rate   |    |    |  1.81  |  % |    |    |  2.78  |  % |     |   Contractual term (years)   |    |    |  10.00  |    |    |    |  10.00  |    |     |   Expected term (years)   |    |    |  4.00  |    |    |    |  4.00  |    |     |   Forfeiture rate   |    |    |  5.00  |  % |    |    |  5.00  |  % |     |   Exercise price (grant-date closing price) per option   |    |  $ |  4.76  |    |    |  $ |  5.90  |    |     |   Fair value per option   |    |  $ |  0.39  |    |    |  $ |  0.49  |    |      
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| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block] | 
  |   |    |   Fiscal Year Ended March 29, 2020    |    |     |   |    |     |    |    |     |    |    |     |     |     |     |   |    |     |    |    |     |    |    |     |    |      Options Granted in Fiscal Year    |    |     |    |    |     |    |    |     |    |     |   2018   |    |  $ |  5  |    |    |  $ |  1  |    |    |  $ |  6  |    |     |   2019   |    |    |  10  |    |    |    |  8  |    |    |    |  18  |    |     |   2020   |    |    |  7  |    |    |    |  11  |    |    |    |  18  |    |     |   |    |    |    |    |    |    |    |    |    |    |    |    |     |   Total stock option compensation   |    |  $ |  22  |    |    |  $ |  20  |    |    |  $ |  42  |    |      
  |   |    |   Fiscal Year Ended March 31, 2019    |    |     |   |    |     |    |    |     |    |    |     |     |     |     |   |    |     |    |    |     |    |    |     |    |      Options Granted in Fiscal Year    |    |     |    |    |     |    |    |     |    |     |   2017   |    |  $ |  6  |    |    |  $ |  4  |    |    |  $ |  10  |    |     |   2018   |    |    |  17  |    |    |    |  26  |    |    |    |  43  |    |     |   2019   |    |    |  7  |    |    |    |  13  |    |    |    |  20  |    |     |   |    |    |    |    |    |    |    |    |    |    |    |    |     |   Total stock option compensation   |    |  $ |  30  |    |    |  $ |  43  |    |    |  $ |  73  |    |      
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| Share-based Payment Arrangement, Option, Exercise Price Range [Table Text Block] | 
  |   |     |     |     |    |     |     |     |    |     |     |     |    |     |    |    |     |     |     |    |     |    |     |   |   |   |     |    |     |   |     |    |     |    |    |     |    |    |     |   |     |    |     |    |     |   |   |   |     |    |     |    |    |     |    |    |     |    |    |     |    |    |     |    |     |    |    |    |     |    |    |     |    |    |     |    |    |     |    |    |     |    |     |    |    |    |     |    |    |     |    |    |     |    |    |     |    |    |     |    |     | $4.00 |  -  |  4.99  |    |    |    |  130,000  |    |    |    |  8.90  |    |    |  $ |  4.76  |    |    |    |  5,000  |    |    |  $ |  4.81  |    |     | $5.00 |  -  |  5.99  |    |    |    |  105,000  |    |    |    |  7.06  |    |    |  $ |  5.81  |    |    |    |  60,000  |    |    |  $ |  5.74  |    |     | $6.00 |  -  |  6.99  |    |    |    |  25,000  |    |    |    |  4.11  |    |    |  $ |  6.21  |    |    |    |  25,000  |    |    |  $ |  6.21  |    |     | $7.00 |  -  |  7.99  |    |    |    |  132,500  |    |    |    |  6.02  |    |    |  $ |  7.81  |    |    |    |  132,500  |    |    |  $ |  7.81  |    |     | $8.00 |  -  |  8.99  |    |    |    |  55,000  |    |    |    |  5.20  |    |    |  $ |  8.38  |    |    |    |  55,000  |    |    |  $ |  8.38  |    |     | $9.00 |  -  |  9.99  |    |    |    |  70,000  |    |    |    |  6.19  |    |    |  $ |  9.60  |    |    |    |  70,000  |    |    |  $ |  9.60  |    |     |   |     |     |    |    |    |  517,500  |    |    |    |  6.80  |    |    |  $ |  6.86  |    |    |    |  347,500  |    |    |  $ |  7.74  |    |      
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| Share-based Payment Arrangement, Nonemployee Director Award Plan, Activity [Table Text Block] | 
  |   |     |    |    |     |    |    |    |    |     |   |     |    |    |     |    |    |     |    |     |   |    |  46,512 |    |    |  $ |  5.16  |    |    |     |    |     |   |    |  28,000 |    |    |    |  5.43  |    |    |     |    |     |   |    |  28,000 |    |    |    |  5.50  |    |    |     |    |     |   |    |  28,000 |    |    |    |  10.08  |    |    |     |    |      
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| Schedule of Nonvested Share Activity [Table Text Block] | 
  |   |    |   Fiscal Year Ended March 29, 2020    |    |     |   |    |     |     |     |    |     |    |    |     |    |      Stock Granted in Fiscal Year    |    |     |    |    |     |    |    |     |    |     |   2018   |    |  $ |  -  |    |    |  $ |  26  |    |    |  $ |  26  |    |     |   2019   |    |    |  73  |    |    |    |  76  |    |    |    |  149  |    |     |   2020   |    |    |  -  |    |    |    |  80  |    |    |    |  80  |    |     |   |    |    |    |    |    |    |    |    |    |    |    |    |     |   Total stock grant compensation   |    |  $ |  73  |    |    |  $ |  182  |    |    |  $ |  255  |    |      
  |   |    |   Fiscal Year Ended March 31, 2019    |    |     |   |    |     |     |     |    |     |    |    |     |    |      Stock Granted in Fiscal Year    |    |     |    |    |     |    |    |     |    |     |   2017   |    |  $ |  -  |    |    |  $ |  47  |    |    |  $ |  47  |    |     |   2018   |    |    |  116  |    |    |    |  77  |    |    |    |  193  |    |     |   2019   |    |    |  13  |    |    |    |  51  |    |    |    |  64  |    |     |   |    |    |    |    |    |    |    |    |    |    |    |    |     |   Total stock grant compensation   |    |  $ |  129  |    |    |  $ |  175  |    |    |  $ |  304  |    |      
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| Performance Shares [Member] | 
 
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| Notes Tables | 
 
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| Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block] | 
  |   |    |     |     |     |    |   
Vesting of shares during the  
fiscal years 
 ended 
    |    |     |    |    |     |     |     |    |     |    |    |     |    |     |    |    |     |    |    |     |    |    |     |    |    |     |    |    |     |    |    |     |    |    |     |    |     |    |    |     |    |    |     |    |    |     |    |    |     |    |    |     |    |    |     |    |    |     |    |     |   2017   |    |    |  41,205  |    |    |    |  -  |    |    |  $ |  -  |    |    |  $ |  -  |    |    |    |  20,601  |    |    |  $ |  122,000  |    |    |  $ |  39,000  |    |     |   2018   |    |    |  42,250  |    |    |    |  21,125  |    |    |    |  109,000  |    |    |    |  17,000  |    |    |    |  21,125  |    |    |    |  124,000  |    |    |    |  56,000  |    |     |   |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |     |   |    |     |    |    |    |  21,125  |    |    |  $ |  109,000  |    |    |  $ |  17,000  |    |    |    |  41,726  |    |    |  $ |  246,000  |    |    |  $ |  95,000  |    |      
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