| 4. Discontinued Operations: Sale of Assets to Infinity Labs SD, Inc. (Details - Discontinued Operations) - USD ($) | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
| Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | |
| Income from discontinued operations, net of tax | $ (24,000) | $ 126,000 | $ 893,000 | $ 252,000 | 
| Micromed Laboratories [Member] | ||||
| Revenues | 0 | 283,000 | 214,000 | 741,000 | 
| Cost of Revenues | 0 | 126,000 | 53,000 | 391,000 | 
| Selling, general and administrative expenses | (1,000) | 31,000 | 38,000 | 98,000 | 
| Income from discontinued operations before tax | 1,000 | 126,000 | 123,000 | 252,000 | 
| Gain (loss) on disposal of discontinued operations before income taxes | (25,000) | 0 | 770,000 | 0 | 
| Total income from discontinued operations, before tax | (24,000) | 126,000 | 893,000 | 252,000 | 
| Income Tax benefit (expense) | 0 | 0 | 0 | 0 | 
| Income from discontinued operations, net of tax | $ (24,000) | $ 126,000 | $ 893,000 | $ 252,000 | 
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- Definition Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of costs of goods sold attributable to disposal group, including, but not limited to, discontinued operation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount of gross profit attributable to disposal group, including, but not limited to, discontinued operation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount of operating expense attributable to disposal group, including, but not limited to, discontinued operation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Details 
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