XML 42 R33.htm IDEA: XBRL DOCUMENT
v3.25.1

Note 3 - Discontinued Operations (Details Textual) - USD ($) |  |  |  |  | 1 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 15, 2026 | Dec. 15, 2025 | Feb. 19, 2025 | Jan. 24, 2025 | Jan. 31, 2025 | Mar. 31, 2025 | Dec. 13, 2024 | Jul. 26, 2024
Seed [Member] | Series A-3 Financing [Member] | Series A-3 Preferred Stock [Member] |  |  |  |  |  |  |  |
Equity Agreement, Aggregate Shares Issuable |  |  |  |  |  |  |  | 5,647,059
Seed [Member] |  |  |  |  |  |  |  |
Investment Owned, Shares Sold |  |  | 1,730,454 | 8,333,637 |  |  |  |
Investment Owned, Shares Sold, Price Per Share |  |  |  | $ 4.25 |  |  |  |
Proceeds from Sale, Maturity and Collection of Investments |  |  | $ 7,354,000 | $ 35,418 | $ 35,418,000 |  |  |
Investment Owned, Net Assets, Percentage |  |  | 40.12% |  |  |  |  |
Noncontrolling Interest, Increase (Decrease) in Ownership Percentage |  |  | 6.75% |  |  |  |  |
Seed [Member] | Forecast [Member] |  |  |  |  |  |  |  |
Investment Owned, Shares Sold | 3,500,128 | 3,103,055 |  |  |  |  |  |
Investment Owned, Net Assets, Percentage | 14.37% | 28.02% |  |  |  |  |  |
Seed [Member] | Winning View Investment Limited [Member] |  |  |  |  |  |  |  |
Investment Owned, Shares Sold |  |  | 980,427 |  |  |  |  |
Seed [Member] | Winning View Investment Limited [Member] | Forecast [Member] |  |  |  |  |  |  |  |
Investment Owned, Shares Sold | 1,750,064 | 1,436,327 |  |  |  |  |  |
Seed [Member] | Full Tech Corporate Development Limited [Member] |  |  |  |  |  |  |  |
Investment Owned, Shares Sold |  |  | 250,009 |  |  |  |  |
Seed [Member] | Full Tech Corporate Development Limited [Member] | Forecast [Member] |  |  |  |  |  |  |  |
Investment Owned, Shares Sold | 583,355 | 555,576 |  |  |  |  |  |
Seed [Member] | Mapfil Investment Limited [Member] |  |  |  |  |  |  |  |
Investment Owned, Shares Sold |  |  | 500,018 |  |  |  |  |
Seed [Member] | Mapfil Investment Limited [Member] | Forecast [Member] |  |  |  |  |  |  |  |
Investment Owned, Shares Sold | 1,166,709 | 1,111,152 |  |  |  |  |  |
Seed [Member] | Minimum [Member] |  |  |  |  |  |  |  |
Investment Owned, Disposal Percentage |  |  |  |  |  | 90.00% | 90.00% |
Seed [Member] | Maximum [Member] |  |  |  |  |  |  |  |
Investment Owned, Disposal Percentage |  |  |  |  |  | 100.00% | 100.00% |

X
- Definition Represents the aggregate shares issuable as part of an equity agreement. + References No definition available. + Details
Name: | bysi_EquityAgreementAggregateSharesIssuable
Namespace Prefix: | bysi_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Represents the percentage of investment owned to be disposed. + References No definition available. + Details
Name: | bysi_InvestmentOwnedDisposalPercentage
Namespace Prefix: | bysi_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Represents the number of shares sold of investment owned during the period. + References No definition available. + Details
Name: | bysi_InvestmentOwnedSharesSold
Namespace Prefix: | bysi_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the price per share of shares sold of an investment owned during the period. + References No definition available. + Details
Name: | bysi_InvestmentOwnedSharesSoldPricePerShare
Namespace Prefix: | bysi_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of change in ownership percentage. + References No definition available. + Details
Name: | bysi_NoncontrollingInterestIncreaseDecreaseInOwnershipPercentage
Namespace Prefix: | bysi_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of investment owned to net assets. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 55 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477439/946-210-55-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-1 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12(Column C)(Footnote 5)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-1 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column D)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-3 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column C)(Footnote 2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-3 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column A)(Footnote 6)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-3 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14(Column F)(Footnote 7)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-6 + Details
Name: | us-gaap_InvestmentOwnedPercentOfNetAssets
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The cash inflow associated with the sale, maturity and collection of all investments such as debt, security and so forth during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-12 + Details
Name: | us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=bysi_SeedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=bysi_SeriesA3FinancingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=bysi_SeriesA3PreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=bysi_SeedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementScenarioAxis=srt_ScenarioForecastMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=bysi_WinningViewInvestmentLimitedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=bysi_FullTechCorporateDevelopmentLimitedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=bysi_MapfilInvestmentLimitedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |