XML 59 R46.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Note 8 - Investments, Including Investments Accounted for Using the Equity Method - Schedule of Investments (Details) - USD ($) | Sep. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Short-term Investments | $ 5,045,851 | $ 1,659,299
Long-term investments | 32,275,045 | 13,901,281
Certificates of Deposit [Member] |  |
Short-term Investments | 868,338 | 746,219
Long-term investments | 898,491 | 1,080,426
US Treasury Securities [Member] |  |
Long-term investments | 2,214,050 | 2,820,855
U.S. Treasury Notes and Corporate Bonds [Member] |  |
Short-term Investments | 4,177,513 | 809,184
Convertible Debt Securities [Member] |  |
Short-term Investments |  | 103,896
Preferred Stock [Member] |  |
Long-term investments | 104,019 |
Non-voting Common Units of LLC [Member] |  |
Long-term investments | 10,000,000 | 10,000,000
Voting Common Stock of Privately Held Company CB&T Holding Corporation [Member] |  |
Long-term investments | $ 19,058,485 |

X
- Definition The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(4)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(1)(g)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_ShortTermInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_CertificatesOfDepositMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=bomn_UsTreasuryNotesAndCorporateBondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_ConvertibleDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_PreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=bomn_NonvotingCommonUnitsOfLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=bomn_VotingCommonStockOfPrivatelyHeldCompanyCBTHoldingCorporationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |