Excess workers' compensation insurance coverage.

No definition available.

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- Definition

Excess workers' compensation insurance coverage maximum limit.

+ References

No definition available.

+ Details

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- Definition

Excess workers' compensation insurance retention.

+ References

No definition available.

+ Details

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- Definition

Insurance Deposit As Security For Future Payment Obligations Under Workers Compensation Program

+ References

No definition available.

+ Details

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- Definition

Letter of credit.

+ References

No definition available.

+ Details

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- Definition

Restricted money market funds and certificates of deposit current.

+ References

No definition available.

+ Details

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- Definition

Specified investment balances.

+ References

No definition available.

+ Details

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- Definition

Specified investment balances increase in surety bond requirement.

+ References

No definition available.

+ Details

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- Definition

Standby letters of credit and a surety bond.

+ References

No definition available.

+ Details

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- Definition

Workers Compensation Claims Maximum Coverage Per Incident

+ References

No definition available.

+ Details

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- Definition

The maximum amount that triggers workers compensation risk transfer through an indemnity agreement.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Carrying value as of the balance sheet date of obligations and payables pertaining to claims incurred of a workers compensation nature.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.15(a))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 15
-Subparagraph 5
-Article 9

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Workers' Compensation Claims - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance in ACE trust account	$ 166,600,000	$ 50,100,000
Estimated future liability for unsettled workers' compensation	255,675,000	225,278,000	$ 121,056,000	$ 78,511,000
Specified investment balances or other financial instruments	156,800,000	$ 198,500,000
Letter of credit	88,300,000
Restricted money market funds, current	92,400,000
California [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increasing Company's surety deposit requirement	147,200,000
Surety bonds and standby letters of credit	152,000,000
Barrett Business Services Inc [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Worker's compensation risk claim	5,000,000
Worker's compensation risk claim maximum	5,000,000
AICE [Member] \| Self-Insured States [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess workers' compensation insurance retention	5,000,000
AICE [Member] \| Maryland [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess workers' compensation insurance retention	1,000,000
AICE [Member] \| Colorado [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess workers' compensation insurance retention	2,000,000
ACE Group [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess workers' compensation insurance coverage with ACE group	5,000,000
ACE Group [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess workers' compensation insurance coverage with ACE group	15,000,000
ACE Group [Member] \| Maryland [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess workers' compensation insurance coverage with ACE group	1,000,000
ACE Group [Member] \| Maryland [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess workers' compensation insurance coverage with ACE group	$ 25,000,000
ACE Group [Member] \| Colorado [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess workers' compensation insurance coverage with American Insurance Company	Statutory limits
ACE Group [Member] \| Colorado [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess workers' compensation insurance coverage with ACE group	$ 2,000,000