Note 8 - Stock-based Compensation and Other Plans (Details Textual) - USD ($) | Aug. 02, 2021 | Feb. 22, 2021 | Jan. 19, 2021 | Aug. 31, 2020 | Mar. 31, 2022 | Mar. 31, 2021 | Jun. 04, 2021 |
Chief Executive Officer [Member] | | | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures, Total (in shares) | | 630,000 | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) | | $ 1.90 | | | | | |
Chief Financial Officer [Member] | | | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures, Total (in shares) | | | | 200,000 | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) | | | | $ 0.85 | | | |
Share-Based Payment Arrangement, Option [Member] | Chief Financial Officer [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | | | | 3 years | | | |
Share-Based Payment Arrangement, Option [Member] | Chief Financial Officer [Member] | Share-Based Payment Arrangement, Tranche One [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage | | | | 25.00% | | | |
SGRP Shares [Member] | Chief Global Commercial Officer [Member] | | | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | 26,882 | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) | $ 1.86 | | | | | | |
SGRP Shares [Member] | Chief Strategy and Growth Officer [Member] | | | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | 26,882 | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) | $ 1.86 | | | | | | |
SGRP Shares [Member] | Chief Executive Officer [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value | | $ 50,000 | | | | | |
Restricted Stock Units (RSUs) [Member] | Chief Global Commercial Officer [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | 1 year | | | | | | |
Share Based Compensation Arrangement by Share Based Payment Award Equity Instruments Other than Options Granted in Period Total Fair Value | $ 50,000 | | | | | | |
Restricted Stock Units (RSUs) [Member] | Chief Strategy and Growth Officer [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | 1 year | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value | $ 50,000 | | | | | | |
Restricted Stock Units (RSUs) [Member] | Chief Executive Officer [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | | 1 year | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | | 26,315 | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) | | $ 1.90 | | | | | |
Share Based Compensation Arrangement by Share Based Payment Award Equity Instruments Other than Options Annual Grant Value | | $ 100,000 | | | | | |
The 2018 Plan [Member] | | | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures, Total (in shares) | | | | | 600,000 | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Ending Balance (in shares) | | | | | 160,000 | | |
The 2018 Plan [Member] | Share-Based Payment Arrangement, Option [Member] | | | | | | | |
Share-Based Payment Arrangement, Expense | | | | | $ 110,000 | $ 96,000 | |
Share-Based Payment Arrangement, Expense, Tax Benefit | | | | | 27,000 | 24,000 | |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total | | | | | 228,000 | | |
The 2018 Plan [Member] | Restricted Stock [Member] | | | | | | | |
Share-Based Payment Arrangement, Expense | | | | | 40,000 | 5,000 | |
Share-Based Payment Arrangement, Expense, Tax Benefit | | | | | 10,000 | $ 1,000 | |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total | | | | | $ 116,000 | | |
The 2021 Plan [Member] | Share-Based Payment Arrangement, Option [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | | | | | 4 years | | |
The 2021 Plan [Member] | SGRP Shares [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) | | | | | | | 400,000 |
The 2021 Plan [Member] | Restricted Stock Units (RSUs) [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) | | | | | | | 150,000 |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | | | | | 58,011 | | |
The 2021 Plan [Member] | Restricted Stock Units (RSUs) [Member] | Share-Based Payment Arrangement, Employee [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | | | | | 3 years | | |
The 2020 Plan [Member] | The 19 Employees [Member] | | | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | | | 125,000 | | | | |
The 2020 Plan [Member] | Director One [Member] | | | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | | | 10,000 | | | | |
The 2020 Plan [Member] | Director Four [Member] | | | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | | | 10,000 | | | | |
The 2020 Plan [Member] | Director Two [Member] | | | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | | | 10,000 | | | | |
The 2020 Plan [Member] | Director Three [Member] | | | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | | | 10,000 | | | | |
The 2020 Plan [Member] | Each Member of Board of Directors [Member] | | | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | | | 50,000 | | | | |
The 2020 Plan [Member] | SGRP Shares [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) | | | 550,000 | | | | |
The 2020 Plan [Member] | SGRP Shares for Each of Up to First Three Additional New Directors During Period December 1, 2020, to April 30, 2021 [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) | | | 50,000 | | | | |
The 2020 Plan [Member] | SGRP Shares for Three Additional New Directors During Period December 1, 2020, to April 30, 2021 [Member] | Maximum [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) | | | 700,000 | | | | |
The 2020 Plan [Member] | SGRP Shares for One Additional New Director On Plan Effective Date [Member] | Maximum [Member] | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) | | | 600,000 | | | | |
The 2008 Plan [Member] | | | | | | | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Ending Balance (in shares) | | | | | 691,162 | | |