Changes in state tax benefit.

No definition available.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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Expiration date of each operating loss carryforward included in operating loss carryforward, in CCYY-MM-DD format.

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)

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-Publisher FASB

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-Glossary Carryforwards

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Expiration date of the tax credit carryforward, in CCYY-MM-DD format.

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 45

-Paragraph 20

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Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Line Items]
Valuation allowance of federal and state tax benefits not expected to be utilized	$ 1,078,000	$ 1,763,000
Additional valuation allowance	0
Unrecognized tax benefits	0us-gaap_UnrecognizedTaxBenefits	0us-gaap_UnrecognizedTaxBenefits
Reduction in state tax benefit	4,000bbsi_ChangesInStateTaxBenefit	284,000bbsi_ChangesInStateTaxBenefit	498,000bbsi_ChangesInStateTaxBenefit
State [Member]
Income Tax Disclosure [Line Items]
Tax credit carry forwards	1,500,000
Tax credit carry forwards expiration date	Dec. 31, 2024
California [Member]
Income Tax Disclosure [Line Items]
Operating loss carry forwards	6,700,000
Operating loss carry forwards expiration date	Dec. 31, 2034
Other States [Member]
Income Tax Disclosure [Line Items]
Operating loss carry forwards	3,900,000
Capital Loss Carry Forward [Member]
Income Tax Disclosure [Line Items]
Tax credit carry forwards	2,100,000
Tax credit carry forwards expiration date	Dec. 31, 2015
Federal General Business Tax Credit Carry Forward [Member]
Income Tax Disclosure [Line Items]
Tax credit carry forwards	3,200,000
Tax credit carry forwards expiration date	Dec. 31, 2024
Alternative Minimum Tax Credit Carry Forward [Member]
Income Tax Disclosure [Line Items]
Tax credit carry forwards	$ 1,800,000
Minimum [Member] \| Other States [Member]
Income Tax Disclosure [Line Items]
Operating loss carry forwards expiration date	Dec. 31, 2021
Maximum [Member] \| Other States [Member]
Income Tax Disclosure [Line Items]
Operating loss carry forwards expiration date	Dec. 31, 2034