XML 84 R71.htm IDEA: XBRL DOCUMENT
v3.22.0.1

Employee Benefit Plans - Summary of Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost (Detail) - Supplemental Employee Retirement Plan [Member] | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Weighted-average assumptions used to determine Net Periodic Benefit Cost |  |
Discount rate | 2.10% | 2.95%
Corridor | 10.00% | 10.00%
Average future working lifetime | 5 years 5 months 4 days | 6 years 5 months 23 days
Mortality table | Pri-2012 WC | Pri-2012
Mortality improvement scale | MP-2020 | MP-2019

X
- Definition Defined benefit plan assumptions used calculating net periodic benefit cost corridor. + References No definition available. + Details
Name: | bbgi_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostCorridor
Namespace Prefix: | bbgi_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Defined benefit plan weighted average assumptions for determining periodic net benefits costs average future working life time. + References No definition available. + Details
Name: | bbgi_DefinedBenefitPlanWeightedAverageAssumptionsForDeterminingPeriodicNetBenefitsCostsAverageFutureWorkingLifeTime
Namespace Prefix: | bbgi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Defined benefit plan weighted average assumptions for determining periodic net benefits costs description of mortality. + References No definition available. + Details
Name: | bbgi_DefinedBenefitPlanWeightedAverageAssumptionsForDeterminingPeriodicNetBenefitsCostsDescriptionOfMortality
Namespace Prefix: | bbgi_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Defined benefit plan weighted average assumptions for determining periodic net benefits costs description of mortality improvement scale. + References No definition available. + Details
Name: | bbgi_DefinedBenefitPlanWeightedAverageAssumptionsForDeterminingPeriodicNetBenefitsCostsDescriptionOfMortalityImprovementScale
Namespace Prefix: | bbgi_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_SupplementalEmployeeRetirementPlanDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |