Amount of commitment of all lenders as condition to maintain minimum fixed charge coverage ratio.

No definition available.

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- Definition

Line of credit facility basis spread on variable rate under condition one.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Line of credit facility basis spread on variable rate under condition three.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	instant

- Definition

Line of credit facility basis spread on variable rate under condition two.

+ References

No definition available.

+ Details

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Namespace Prefix:	kfrc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of additional borrowing capacity through amendment on a line of credit.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of credit facility maximum borrowing percentage of accounts receivable.

+ References

No definition available.

+ Details

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Namespace Prefix:	kfrc_
Data Type:	num:percentItemType
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Period Type:	instant

- Definition

Line of credit facility maximum borrowing percentage of employee placement accounts.

+ References

No definition available.

+ Details

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Namespace Prefix:	kfrc_
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Balance Type:	na
Period Type:	instant

- Definition

Line of credit facility maximum borrowing percentage of unbilled accounts receivable.

+ References

No definition available.

+ Details

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Namespace Prefix:	kfrc_
Data Type:	num:percentItemType
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Period Type:	instant

- Definition

Line of credit facility sub-limit for letters of credit.

+ References

No definition available.

+ Details

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Namespace Prefix:	kfrc_
Data Type:	xbrli:monetaryItemType
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- Definition

Line of Credit Facility, Covenant, Limit on Distributions, Availability of Borrowing Capacity

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Line of Credit Facility, Covenant, Limit on Distributions, Maximum Percent Availability of Borrowing Capacity

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Limit on Equity Security Repurchases, Availability of Borrowing Capacity

+ References

No definition available.

+ Details

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Namespace Prefix:	kfrc_
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Period Type:	instant

- Definition

Line of Credit Facility, Limit on Equity Security Repurchases, Maximum Percent Availability of Borrowing Capacity

+ References

No definition available.

+ Details

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Namespace Prefix:	kfrc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility Maximum Borrowings Percentage of Corporate Headquarters

+ References

No definition available.

+ Details

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Namespace Prefix:	kfrc_
Data Type:	num:percentItemType
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Period Type:	instant

- Definition

Line of Credit Facility, Unused Capacity, Commitment Fee Percentage, Threshold

+ References

No definition available.

+ Details

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Namespace Prefix:	kfrc_
Data Type:	num:percentItemType
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Period Type:	duration

- Definition

Percentage of commitment of all lenders as condition to maintain minimum fixed charge coverage ratio.

+ References

No definition available.

+ Details

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- Definition

Quarterly Reduction of Additional Corporate Headquarters Borrowing Base

+ References

No definition available.

+ Details

Name:	kfrc_QuarterlyReductionofAdditionalCorporateHeadquartersBorrowingBase
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Data Type:	num:percentItemType
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Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

+ Details

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Period Type:	duration

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=28361426&loc=d3e1314-112600

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=28361426&loc=d3e1336-112600

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Line-of-Credit Arrangement
-URI http://asc.fasb.org/extlink&oid=6517033

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Credit Facility - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2016	Apr. 29, 2016	Apr. 15, 2016	Dec. 31, 2015
Line of Credit Facility [Line Items]
Percentage of accounts receivable	85.00%
Percentage of unbilled accounts receivable	85.00%
Percentage of employee placement accounts	80.00%
Interest rate terms	Outstanding borrowings under the Revolving Loan Amount bear interest at a rate of: (a) LIBOR plus an applicable margin based on various factors; or (b) the higher of (1) the prime rate, (2) the federal funds rate plus 0.50% or (3) LIBOR plus 1.25%.
Percentage of interest rate under revolving loan amount, condition 1	1.25%
Percentage of interest rate under revolving loan amount, condition 2	0.50%
Percentage of interest rate under revolving loan amount, condition 3	0.125%
Percentage of aggregate amount of the commitment	10.00%
Minimum availability under credit facility to avoid negative covenants	$ 11,000,000
Long-term debt – credit facility	103,454,000			$ 80,472,000
Credit facility remaining borrowing capacity	42,000,000
Subsequent Event
Line of Credit Facility [Line Items]
Maximum borrowings percentage of corporate headquarters			80.00%
Quarterly reduction of additional borrowings, as a percent			1.25%
Revolving Credit Facility
Line of Credit Facility [Line Items]
Borrowing capacity under credit facility	170,000,000
Remaining credit facility under accordion option	$ 50,000,000
Unused credit facility commitment fee percentage threshold	35.00%
Maximum percent availability of borrowing capacity	15.00%
Availability of borrowing capacity	$ 15,000,000
Covenant limit on distributions and equity repurchases percent	12.50%
Covenant limit on distributions and equity repurchases	$ 20,600,000
Revolving Credit Facility \| Subsequent Event
Line of Credit Facility [Line Items]
Amount outstanding under Credit Facility		$ 108,600,000
Credit facility remaining borrowing capacity		$ 44,900,000
Revolving Credit Facility \| Below Threshold
Line of Credit Facility [Line Items]
Unused credit facility commitment fee percentage	0.35%
Revolving Credit Facility \| Above Threshold
Line of Credit Facility [Line Items]
Unused credit facility commitment fee percentage	0.25%
Letter of Credit
Line of Credit Facility [Line Items]
Sub-limit under credit facility for letters of credit	$ 15,000,000