XML 37 R35.htm IDEA: XBRL DOCUMENT
v2.4.1.9

ACQUISITIONS AND DISPOSITION (Details) (USD $) | 3 Months Ended | 0 Months Ended |
--- | --- | --- | ---
Mar. 31, 2015 | Mar. 31, 2014 | Jan. 23, 2015 | Jun. 19, 2014 | Jun. 19, 2014 | Jul. 25, 2014 | Dec. 31, 2014
Business Acquisition and Disposition [Line Items] |  |  |  |  |  |  |  |
Revenues | $ 142,015,000 us-gaap_SalesRevenueGoodsNet | $ 82,646,000 us-gaap_SalesRevenueGoodsNet |  |  |  |  |  |
Operating income | 9,359,000 us-gaap_OperatingIncomeLoss | 2,881,000 us-gaap_OperatingIncomeLoss |  |  |  |  |  |
Liabilities assumed [Abstract] |  |  |  |  |  |  |  |
Goodwill | 117,678,000 us-gaap_Goodwill |  |  |  |  |  |  | 117,573,000 us-gaap_Goodwill
Network Power Systems [Member] |  |  |  |  |  |  |  |
Business Acquisition and Disposition [Line Items] |  |  |  |  |  |  |  |
Revenues |  |  | 900,000 us-gaap_SalesRevenueGoodsNet / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = belfb_NetworkPowerSystemsMember |  |  |  |  |
Disposition Sale of NPS [Abstract] |  |  |  |  |  |  |  |
Proceeds from sale of business |  |  | 9,000,000 us-gaap_ProceedsFromDivestitureOfBusinesses / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = belfb_NetworkPowerSystemsMember |  |  |  |  |
Proceeds from sale of business in escrow |  |  | 1,000,000 belfb_ProceedsFromSaleOfBusinessInEscrow / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = belfb_NetworkPowerSystemsMember |  |  |  |  |
Number of months of manufacturing service agreement |  |  | 24 months |  |  |  |  |
Deferred revenue |  |  | 9,000,000 us-gaap_DeferredRevenue / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = belfb_NetworkPowerSystemsMember |  |  |  |  |
Power Solutions [Member] |  |  |  |  |  |  |  |
Business Acquisition and Disposition [Line Items] |  |  |  |  |  |  |  |
Payment for acquisitions, net of cash acquired |  |  |  |  | 109,900,000 us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Percentages of owned joint venture investment (in hundredths) |  |  |  | 49.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 49.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Assets acquired [Abstract] |  |  |  |  |  |  |  |
Cash |  |  |  | 20,912,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 20,912,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Accounts receivable |  |  |  | 29,389,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 29,389,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Inventories |  |  |  | 36,429,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 36,429,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Other current assets |  |  |  | 7,350,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 7,350,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Property, plant and equipment |  |  |  | 28,175,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 28,175,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Intangible assets |  |  |  | 33,220,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 33,220,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Other assets |  |  |  | 19,171,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 19,171,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Total identifiable assets |  |  |  | 174,646,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 174,646,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Liabilities assumed [Abstract] |  |  |  |  |  |  |  |
Accounts payable |  |  |  | (26,180,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | (26,180,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Accrued expenses |  |  |  | (25,545,000)belfb_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpenses / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | (25,545,000)belfb_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpenses / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Other current liabilities |  |  |  | 223,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 223,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Noncurrent liabilities |  |  |  | (42,062,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | (42,062,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Total liabilities assumed |  |  |  | (93,564,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | (93,564,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Net identifiable assets acquired |  |  |  | 81,082,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 81,082,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Goodwill |  |  |  | 49,710,000 us-gaap_Goodwill / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 49,710,000 us-gaap_Goodwill / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Net assets acquired |  |  |  | 130,792,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember | 130,792,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |
Consideration transferred [Abstract] |  |  |  |  |  |  |  |
Cash Paid |  |  |  | 130,792,000 us-gaap_PaymentsToAcquireBusinessesGross / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |  |
Assumption of liability |  |  |  | 0 us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |  |
Fair value of consideration transferred |  |  |  | 130,792,000 us-gaap_BusinessCombinationConsiderationTransferred1 / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |  |
Deferred consideration |  |  |  | 0 belfb_BusinessCombinationContingentConsiderationAtFairValue / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |  |
Total consideration paid |  |  |  | 130,792,000 belfb_BusinessCombinationCostOfAcquiredEntityPurchasePrice / us-gaap_BusinessAcquisitionAxis = belfb_PowerSolutionsMember |  |  |  |
2014 Acquired Companies [Member] |  |  |  |  |  |  |  |
Business Acquisition and Disposition [Line Items] |  |  |  |  |  |  |  |
Acquisition-related costs | 400,000 us-gaap_BusinessCombinationAcquisitionRelatedCosts / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member |  |  |  |  |  |  |
Revenues | 58,800,000 us-gaap_SalesRevenueGoodsNet / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member |  |  |  |  |  |  |
Operating income | 5,900,000 us-gaap_OperatingIncomeLoss / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member |  |  |  |  |  |  |
Unaudited Pro forma Consolidated Results of Operations [Abstract] |  |  |  |  |  |  |  |
Revenue |  | 160,637,000 us-gaap_BusinessAcquisitionsProFormaRevenue / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member |  |  |  |  |  |
Net earnings |  | 1,658,000 us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member |  |  |  |  |  |
2014 Acquired Companies [Member] | Acquisition Date Fair Values (As adjusted) [Member] |  |  |  |  |  |  |  |
Assets acquired [Abstract] |  |  |  |  |  |  |  |
Cash | 27,456,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Accounts receivable | 38,764,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Inventories | 54,061,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Other current assets | 9,965,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Property, plant and equipment | 38,075,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Intangible assets | 73,220,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Other assets | 21,516,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Total identifiable assets | 263,057,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Liabilities assumed [Abstract] |  |  |  |  |  |  |  |
Accounts payable | (36,862,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Accrued expenses | (30,852,000)belfb_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpenses / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Other current liabilities | 166,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Noncurrent liabilities | (59,376,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Total liabilities assumed | (126,924,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Net identifiable assets acquired | 136,133,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Goodwill | 100,016,000 us-gaap_Goodwill / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Net assets acquired | 236,149,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Consideration transferred [Abstract] |  |  |  |  |  |  |  |
Cash Paid | 236,149,000 us-gaap_PaymentsToAcquireBusinessesGross / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Assumption of liability | 0 us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Fair value of consideration transferred | 236,149,000 us-gaap_BusinessCombinationConsiderationTransferred1 / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Deferred consideration | 0 belfb_BusinessCombinationContingentConsiderationAtFairValue / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
Total consideration paid | 236,149,000 belfb_BusinessCombinationCostOfAcquiredEntityPurchasePrice / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementScenarioAxis = us-gaap_ScenarioActualMember |  |  |  |  |  |  |
2014 Acquired Companies [Member] | Class A [Member] |  |  |  |  |  |  |  |
Unaudited Pro forma Consolidated Results of Operations [Abstract] |  |  |  |  |  |  |  |
Earnings per common share - basic and diluted (in dollars per share) |  | $ 0.13 belfb_BusinessAcquisitionProFormaEarningsPerShareBasicAndDiluted / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember |  |  |  |  |  |
2014 Acquired Companies [Member] | Class B [Member] |  |  |  |  |  |  |  |
Unaudited Pro forma Consolidated Results of Operations [Abstract] |  |  |  |  |  |  |  |
Earnings per common share - basic and diluted (in dollars per share) |  | $ 0.15 belfb_BusinessAcquisitionProFormaEarningsPerShareBasicAndDiluted / us-gaap_BusinessAcquisitionAxis = belfb_AcquiredCompanies2014Member / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember |  |  |  |  |  |
Connectivity Solutions [Member] |  |  |  |  |  |  |  |
Business Acquisition and Disposition [Line Items] |  |  |  |  |  |  |  |
Payment for acquisitions, net of cash acquired |  |  |  |  |  | 98,800,000 us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember |  |
Assets acquired [Abstract] |  |  |  |  |  |  |  |
Cash |  |  |  |  |  | 6,544,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Accounts receivable |  |  |  |  |  | 9,375,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Inventories |  |  |  |  |  | 17,632,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Other current assets |  |  |  |  |  | 2,615,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Property, plant and equipment |  |  |  |  |  | 9,900,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Intangible assets |  |  |  |  |  | 40,000,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Other assets |  |  |  |  |  | 2,345,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Total identifiable assets |  |  |  |  |  | 88,411,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Liabilities assumed [Abstract] |  |  |  |  |  |  |  |
Accounts payable |  |  |  |  |  | (10,682,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Accrued expenses |  |  |  |  |  | (5,307,000)belfb_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpenses / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Other current liabilities |  |  |  |  |  | (57,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Noncurrent liabilities |  |  |  |  |  | (17,314,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Total liabilities assumed |  |  |  |  |  | (33,360,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Net identifiable assets acquired |  |  |  |  |  | 55,051,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Goodwill |  |  |  |  |  | 50,306,000 us-gaap_Goodwill / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Net assets acquired |  |  |  |  |  | 105,357,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Consideration transferred [Abstract] |  |  |  |  |  |  |  |
Cash Paid |  |  |  |  |  | 105,357,000 us-gaap_PaymentsToAcquireBusinessesGross / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Assumption of liability |  |  |  |  |  | 0 us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Fair value of consideration transferred |  |  |  |  |  | 105,357,000 us-gaap_BusinessCombinationConsiderationTransferred1 / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Deferred consideration |  |  |  |  |  | 0 belfb_BusinessCombinationContingentConsiderationAtFairValue / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
Total consideration paid |  |  |  |  |  | $ 105,357,000 belfb_BusinessCombinationCostOfAcquiredEntityPurchasePrice / us-gaap_BusinessAcquisitionAxis = belfb_EmersonNetworkPowerConnectivitySolutionsMember | [1] |
[1] | The Company acquired the U.S. and U.K. entities of Connectivity Solutions on July 25, 2014 and the China entity of Connectivity Solutions on August 29, 2014. These values represent the estimated fair values as of the respective acquisition dates.

X
- Definition The pro forma basic and diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. + References No definition available. + Details
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