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Investment (Details Textual) (USD $)
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3 Months Ended |
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Mar. 31, 2015
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| Qualstar [Member] | |
| Investment Owned, Balance, Shares (in shares) | 3,095,875us-gaap_InvestmentOwnedBalanceShares / dei_LegalEntityAxis = bkfg_QualstarMember |
| Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum | 25.27%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMaximum / dei_LegalEntityAxis = bkfg_QualstarMember |
| Investment Owned, at Fair Value (in dollars) | $ 705,000us-gaap_InvestmentOwnedAtFairValue / dei_LegalEntityAxis = bkfg_QualstarMember |
| Investment Owned, Face Amount (in dollars) | 4,600,000us-gaap_InvestmentOwnedUnderlyingFaceAmountAtMarketValue / dei_LegalEntityAxis = bkfg_QualstarMember |
| Equity Method Investment, Realized Gain (Loss) on Disposal | 62,000us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal / dei_LegalEntityAxis = bkfg_QualstarMember |
| Interlink Electronics [Member] | |
| Investment Owned, Balance, Shares (in shares) | 691,020us-gaap_InvestmentOwnedBalanceShares / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = bkfg_InterlinkElectronicsIncMember |
| Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum | 11.80%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMaximum / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = bkfg_InterlinkElectronicsIncMember |
| Investment Owned, at Fair Value (in dollars) | 2,500,000us-gaap_InvestmentOwnedAtFairValue / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = bkfg_InterlinkElectronicsIncMember |
| Investment Owned, Face Amount (in dollars) | 6,200,000us-gaap_InvestmentOwnedUnderlyingFaceAmountAtMarketValue / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = bkfg_InterlinkElectronicsIncMember |
| Equity Method Investment, Realized Gain (Loss) on Disposal | $ 93,000us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = bkfg_InterlinkElectronicsIncMember |
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- Definition
Amount of gain (loss) on sale or disposal of an equity method investment. No definition available.
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- Definition
Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Balance held at close of period in number of shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Nominal or face amount on the investment owned. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock. No definition available.
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- Details
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- Details
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